Troubleshooting Guide

Table of contents

Client Troubleshooting Checklist

  1. Did the client fail to download?
        Did the client fail to download using Internet Explorer?
        Did the client fail to download using Netscape?
  2. Is the Host On-Demand desktop appearing very slowly?
  3. Did the client receive an unexpected login prompt?
  4. Did installing the cached client fail using Mozilla?
  5. Did the client download slowly?
  6. Did you receive an online revocation server error?
  7. Are you having trouble loading the client applets or HODAdmin.html using Netscape?
  8. Did you receive an error using the User Profile Manager on Netscape browsers with the Locally installed client?
  9. Does repeatedly logging on and off Host On-Demand clients using Netscape cause the Host On-Demand clients to function improperly?
  10. Are you running multiple sessions when using Netscape and Windows 95 or 98?
  11. Are you having trouble saving session configuration changes?
  12. Are you having trouble using the Shift-Reload key combination to reload the Host On-Demand HTML file?
  13. Did you receive a LOG0001 message?
  14. Have you determined if a port is accessible?
  15. Did you have problems while the IME keypad overlapped a session window (DBCS)?
  16. Did your application fail to recognize the ATTN key value?
  17. Are you waiting a long time for the cached client to download on OS/2?
  18. Are you unable to select the saved file list when using file transfer under Netscape 4.x in Red Flag Linux 3.0?
  19. Did resizing your Netscape 4.x browser on a Linux client cause you to log off HODAdmin?
  20. Is the Host On-Demand Service Manager unable to use LDAP?
  21. Are there exceptions in the Java Console after you refresh the screen using Netscape Version 6?
  22. Did Host On-Demand stop working after installing WebSphere Studio Application Developer - Integrated Edition?
  23. Are you not able to enter your user ID or password on client login panel?
  24. Did you encounter a gray screen when clicking the Users/Groups task on the cached administration client?
  25. Did a customer-supplied applet fail to run with a Java 2-enabled browser?

Did the client fail to download?

If the client does not download, try the following:

  1. Use the Remove Cached Client function under Utilities from the HODMain.html Web page to remove the Cached client or Administrator client, then try to download the client again.
  2. Check that the zSeries Web server has been configured correctly for Host On-Demand files. For example, the *.js and the *.js files should be defined so that they are served as ASCII on zSeries. Refer to your Web server documentation for information regarding defining files.
  3. Check that all the files and directories under the .../hod/ directory have read, write, and execute permissions. For example, on zSeries, you can use CHMOD filename 755 to set the correct permissions on the file filename. Also check /HODDATA/ and its subdirectories for the correct file permissions.
  4. Check the client workstation to make sure there is enough space on the workstation disk to store the Download or Cached client. Refer to you operating system documentation for more information.
  5. Check to see if you have multiple Java 2 plug-ins.

    You may have more than one Java 2 plug-in installed at the same time in your Windows operating system environment. Although you can control which plug-in level is active, we recommended that you have only one Java 2 plug-in installed when using the Host On-Demand cached client. To find out which plug-in is active, open the Windows Control Panel and double click the Java 2 plug-in Control Panel icon. Usually, you can control which Java 2 level is active on the Advanced tab, although the location may vary with different levels of Java 2.

    While most configurations with multiple Java 2 plug-ins will work, if you are having problems with the Host On-Demand cached client and you have multiple Java 2 plug-ins installed, follow these steps:

    1. Uninstall all the Java 2 plug-ins.
    2. Install the Java 2 plug-in that you want to use with the Host On-Demand cached client.

  6. For Microsoft IIS 6.0/ Win 2003 Server, verify that you have enabled all the required MIME types for the files that ship with Host On-Demand. To identify which file types lack MIME entries, review the Web server log file. Any Web server errors of 404 3 indicate the file is lacking a MIME entry. The MIME type should be added as application/octet/stream.
  7. If the Host On-Demand cached client or download client fails to download completely, such that only the Host On-Demand banner graphic and an empty (without session icons) gray Host On-Demand desktop area is displayed, or if an error message is displayed such as 'Downloaded file does not match signature', then the cause of the problem may be that the server is timing out and aborting the download. That is, because the data to be downloaded is large and because the client may be slow, a timeout value in the server associated with the download may be exceeded, causing the server to cancel the download. If this happens, make sure the Web server configuration values are large enough to allow the client the time necessary to download over the network. We suggest the following timeout values as a starting point for HTTP Web servers that are using Host On-Demand. You may need to adjust these values based on your experience and network environment. Refer to your Web server documentation for more information on setting timer values.
  8. If you are using Websphere Applications Server 3.5.4 on a Windows operating system, try updating the IBM HTTP Web server component to service update 1.3.12.6 or higher.
  9. Check that port 8999, if you are using the Configuration Server, is open from the client to the Service Manager machine through the network and all the firewalls in between. Refer to your firewall documentation for more information.
  10. Check the client browser's JVM level to see if it is at a supported level listed in the Planning, Installing, and Configuring Host On-Demand guide or the Readme. If the JVM level is not correct, upgrade to a higher JVM level and try again.
  11. Check the Web server logs for any messages issued during the download time period. Refer to your Web server documentation for more information.
  12. Use CTRL-F5, or click Refresh while holding down the shift key to force Internet Explorer to reload the page. Click Reload button while holding down the shift key to force Netscape to reload the page.
  13. Check proxy server definitions in the browser. Make sure the browser is using a valid proxy server.

    For Netscape:

    1. Select Edit > Preferences from the main menu.
    2. Click Advanced.
    3. Click Proxies. Confirm that the information is correct, or edit the information.
    4. Click OK when you are finished.

    For Internet Explorer:

    1. Select Tools > Internet Preferences from the main menu.
    2. Click the Connections tab to view connection information.
    3. Click LAN Settings. Confirm that the information is correct, or edit the information.
    4. Click OK when you are finished.
  14. Do you say Yes to trust content from International Business Machines when prompted?
  15. Check whether a proxy setting is being used in the Internet Explorer LAN settings.
  16. Make sure that the browser has Java Scripting turned on and that the firewall does not block Java scripts. Host On-Demand clients use Java scripting.

    For Internet Explorer, Select Tools > Internet Options and click the Secuity tab. For the Web content zone field, select Internet if the Host On-Demand system is accessed via the Internet, otherwise select Local intranet. Next, click the Custom Level button and enable the Scripting options.

  17. Check whether a program that disables pop-up messages has been installed on the client machine. Host On-Demand issues pop-up messages, so disabling pop-ups can cause Host On-Demand to stop processing.

Did the client fail to download using Internet Explorer?

If you are having difficulty loading a Host On-Demand client under Internet Explorer, follow the steps in this section to resolve the problem.

Note: The following steps do not require you to be connected to the Internet. The purpose of these steps is to reset Internet Explorer to the correct state to allow the Host On-Demand client to load.

  1. Clear the browser cache. For Java 1, from the Internet Explorer Toolbar, select Tools > Internet Options, and then select Delete files. Be sure to check 'all offline content'. For Java 2, launch the Java Plug-in Control Panel, click the Cache tab and then the Clear button to delete any files that have been cached.
  2. In the same Internet Options window, select Settings, then point to View objects and make sure there is no Host On-Demand object installed. These objects would have names such as 'Host On-Demand 4.0'.
  3. In the same Internet Options window, select Content and then point to Publishers. Delete International Business Machines from the list of trusted publishers.
  4. In the same Internet Options window, select Advanced, then select Restore Defaults. Click Apply and then OK.
  5. Enable the Internet Explorer Java Console. In the Same Internet Options window, click Advanced.
    1. Scroll down to the Microsoft VM section and click the three checkboxes in this section. Select the following three options:
      • Java Console Enabled
      • JIT Compiler for Virtual Machine Enabled
      • Java Logging Enabled
    2. Click Apply.
  6. Check for the browser proxy settings:
    1. Choose the Connections property page
    2. If Use a Proxy Server is checked, record the values set for proxy server on this panel.
    3. Select Advanced.
    4. On the Proxy Settings panel, record the values (if any) for the proxy address being used for each of the proxies listed.
    5. Click OK.
    6. Click OK.
    7. Click OK.

  7. On the Internet Explorer toolbar, select Help and then select About Internet Explorer. What version of IE are you using? Record this information for later use.
  8. Exit out of Internet Explorer and select My Computer on your desktop
  9. Right-mouse click your hard drive and make sure there is sufficient space for the client on your hard drive (5MB should be sufficient). Click File > Properties to determine how much disk space is available.
  10. Use the Remove Cached Client utility from the HODMain.html page, then delete any remaining partially installed files from Host On-Demand Version 5 or Version 6 clients such as the following:
    Note: Deleting these files removes your user preferences and any recorded macros.

    To find out if these files exist on your PC, go to the Start menu, select Search, select Files Or Folders, type the name of the file/folder you want to search for in the Named box, select to search all your drives in the Look In box, and then click Find Now.

  11. Go to Start, select Settings, and then select Control Panel. Click Add/Remove programs and select Internet Explorer. Choose the REPAIR option.
  12. Exit out of the control program and back to your normal Desktop.
  13. Restart your PC.
    Note: This option may not be available if you are using Windows 2000 SP2. Check the Microsoft Web site on how to repair Internet Explorer when you are using Windows 2000.
  14. You may want to check the Microsoft Web site for the latest Microsoft JVM, and if it is a later version than the one you are currently using, install it.

    To display the Java Console and determine the level of Java you are currently running, select View on the Internet Explorer Toolbar, then point to the Java Console. The Java Console window appears. The level is the last four digits as seen in the first line of the Java Console. For example:

    Microsoft (R) VM for Java, 5.0 Release 5.0.0.3805

    If you decide to upgrade the code on your machine, download the build from the Microsoft Web site and save it on your PC. When the download is complete, close the browser, double click on the downloaded file, and follow the instructions for installing the JVM. You need to restart your PC to complete the installation process

    Note: Reinstalling the latest JVM sometimes resolves problems if nothing else has worked.

Did the client fail to download using Netscape?

Note: These steps do not require you to be connected to the Internet. The purpose of these steps is to reset Netscape Navigator to the correct state to allow the Host On-Demand client to load.

  1. Use the Remove Cached Client utility from the HODMain.html page, then delete any remaining partially installed files from Host On-Demand Version 5 or Version 6 clients such as the following:

    For clients running Java 2, launch the Java Plug-in Control Panel, click the Cache tab and then the Clear button to delete any files that have been cached.

    Note: Deleting these files removes your user preferences and any recorded macros.

    To find out if these files exist on your PC, select each of your listed hard drives under My Computer. Right-mouse click on the drive and select Search. Now search for each of the files/folders listed above. When you find one of these files, delete it.

  2. Exit out of My Computer and back to the Desktop.
  3. Try doing a Shift+F9 or Shift+Refresh after loading the client.
  4. Delete temporary Internet files. Select Edit from the toolbar, select Preferences, select Advanced, and then select Clear Disk Cache.
  5. Record any proxy settings with which you have configured the browser. To do this, select Edit from the toolbar, select Preferences, and then select Advanced. Point to Proxies and record any proxy settings on this panel. If Manual proxy configurations is selected, then select View. Record all the values you have configured on this page.

Is the Host On-Demand desktop appearing very slowly?

When there are 20 or more defined sessions, sometimes the Host On-Demand desktop may appear very slowly. The problem might be caused by the the amount of time it takes to process the large number of defined sessions (not the host connection or the loading of the cached client). To prevent the delay using the HTML-based model, try the following steps:

  1. Divide the commonly-used sessions into smaller, separate groups, with one group per HTML file according to the users' requirements. This reduces loading time. If most of the sessions are randomly needed, move to the next step.
  2. Group the primary sessions together in one HTML file, adding one or two additional sessions that do not have the target host system defined (in properties). This allows individual users to define the target systems by using the Properties dialog box. Using this method, Host On-Demand remembers the session, but a user can change the session at any time.
Did the client receive an unexpected login prompt?

When using the HTML-based or Combined models, the Host On-Demand client defaults to prompting for a Host On-Demand user ID and password if the Deployment Wizard files are not received from the Web server, or if they are not received in the expected format. Take the following steps to avoid this.

  1. Check that all the HTML files and all the /HODData/*.* files are loaded to the server. The HTML files must be in the publish directory, and the /HODData/ directory must be located under the Host On-Demand publish directory.
  2. Make sure the /HODData and your HTML file names are spelled correctly and have the correct upper and lower case characters in the name.
  3. For zSeries (S/390 or zOS), check the following:
    1. Check that all the HTML files have .ascii appended to the name. (*.html.ascii)
    2. Check that all the TXT files in the /HODData/yourhtmlname directory have .ascii appended to them.
    3. Check that the files in the HODData/yourhtmlname/*.* subdirectory have read, write, and execute permissions (also known as 755).
    4. Check that the files were uploaded as binary files to the Web server.
    5. Check for any Web server directives that might cause the request from the Host On-Demand client to be redirected or to download incorrectly.
Did installing the cached client fail using Mozilla?

With the Mozilla browser, if nothing happens when you try to install the cached client, or if the attempt to install the cached client fails, check the browser configuration. Make sure that Mozilla is not configured to suppress popup windows that appear on top of or under the Navigator window. This setting prevents the Host On-Demand cached client from being installed.

This location of this setting depends on the version of Mozilla:

After the cached client is installed you can restore this setting to suppress popup windows. But if you need to install the entire cached client again, you must again set Mozilla so that it does not suppress popup windows.

The setting to suppress popup windows does not hinder the following operations with the cached client:

Did the client download slowly?

If the client downloads slowly, try the following:

  1. Check to see if other network traffic is also slow.
  2. Make sure other pages are not also downloading slowly. Try to download a non-Host On-Demand HTML file to see if the problem is a Web server problem. If it is a Web server problem, refer to your Web server documentation for more information.
  3. Check to see if port 8999 is active, if you are using the Service Manager to manage user configurations. The client may be trying to connect back to the Service Manager, using processor resources and therefore slowing any downloads. If the port is not active, activate it. Refer to the server's operating system documentation for more information regarding ports.
  4. If this is a dial-up connection, you can use the Host On-Demand Deployment Wizard to create a smaller Download or Cached client with only the features your users need to use.
  5. Check the Web server logs for errors.

Did you receive an online revocation server error?

You may see a security warning with the following error message when installing the Host On-Demand cached client using Internet Explorer:

An error occurred while accessing the online revocation server. 

This error message occurs when the Certificate Revocation option in Internet Explorer is selected. You will be unable to connect to the server to verify that the certificate has not been revoked. To prevent this message, disable the option by selecting Internet Options > Advanced > Security and unchecking "Check for Publisher's Certificate Revocation".

Are you having trouble loading the client applets or HODAdmin.html using Netscape?

If you are using Netscape and cannot load any of the client applets after loading HODAdmin.html, or vice versa, try the following:

Did you receive an error using the User Profile Manager on Netscape browsers with the Locally installed client?

If you receive the following error when using the User Profile Manager on Netscape browsers while loading the Locally installed client from the Start menu,

Cannot find the file C:\hostondemand\HOD_en.html (or one of its components). Make sure the path and
file name are correct and that all required libraries are available.
click OK and the Locally installed client will load in the browser.

Does repeatedly logging on and off Host On-Demand clients using Netscape cause the Host On-Demand clients to function improperly?

Logging on and off any of the Host On-Demand clients repeatedly without restarting the Netscape browser first can cause the browser to remove files from cache that are needed in order for the clients to function properly. The browser removes files in order to reduce the cache. Restart your browser after logging off and before logging on to any Host On-Demand clients while using Netscape to prevent problems with the clients.

Are you running multiple sessions when using Netscape and Windows 95 or 98?

Due to a restriction in the Netscape browser on Windows 95 and 98, you can start a maximum of 10 to 12 Host On-Demand sessions before Netscape runs out of resources.

Are you having trouble saving session configuration changes?

When using a Host On-Demand session, in order to save session configuration changes such as screen size and colors, right click on the session's green screen and select Save.

Are you having trouble using the Shift-Reload key combination to reload the Host On-Demand HTML file?

If you use Netscape 4.7x with the cached client, avoid using the key combination Shift-Reload to reload the Host On-Demand HTML page. If you use this key combination, the Host On-Demand applet cannot load and you must restart your browser. Close your browser, restart it, and point it to the Host On-Demand server to continue.

Did you receive a LOG0001 message?

If you get a Log0001 message, try the following steps:

  1. A LOG0001 could be caused by a problem at the client machine. Check for Java errors or exceptions in the Java Console, TCP/IP errors in the network reaching the Service Manager machine, or caused by a mix of Host On-Demand download/cached clients. Use HODRemove.html to remove the Cached client.
  2. A LOG0001 could also be caused a problem at the Host On-Demand Service Manager machine. Check for a system abend, looping task, hung tasks, Java abends, check for error messages in NCoDServices.RAS.TXT.
  3. If there are no messages and the client appears to connect, check to see if all the Web server, Host On-Demand, and Telnet ports are active (especially port 8999).

Have you determined if a port is accessible?

Use Telnet or Netstat to determine if a port is accessible. Do the following:

  1. Type Netstat -a at a command line to see if the ports are active. If not, refer to your operating system documentation for information regarding activating ports.
  2. Check for messages in Host On_Demand message and trace log NCoDServices.RAS.txt, located in the \private directory.
  3. Check to see if a port on the Service Manager or through the firewall is active. For example, under Windows NT, use Telnet on the Windows client workstation:
    1. Click Start > Run.
    2. Type telnet and click OK.
    3. Click Connect > Remote system on the Telnet window menu bar.
    4. Type the host name you want to connect to in the Host Name field on the Connect window.
    5. Type 8999 (or other ports based on the problem) in the Port field on the Connect window.
    6. Accept the default TermType.
    7. Click Connect.

    If you receive no messages, the port is open. If you receive Connect failed with 'Host name', then the port is not active. Remember to disconnect after you test each port by selecting Connect > Disconnect from the Telnet window menu.

Refer to your operating system documentation for instructions regarding how to run Telnet on other operating systems.

Did you have problems while the IME keypad overlapped a session window (DBCS)?

If the IME keypad overlaps a Host On-Demand session window, you may get incorrect results when you click the mouse in the keypad.

Did your application fail to recognize the ATTN key value?

The ATTN key value might not be recognized by some applications. If not, you can use the ATTN key parameter to specify the byte stream sent to the server when the ATTN key is pressed.

The syntax for the ATTN key parameter is:

<PARAM Name=attnKeyOverride VALUE=dddd>

When a session is connected in basic TN3270 mode, Host On-Demand sends the following commands to the telnet server when the ATTN key is pressed: PA1, IAC, EOR, IAC, BREAK (in hexadecimal form: 6CFFEFFFF3)

PA1 is the SNA AID key value for the PA1 key. This ATTN key value is the same default value used by Personal Communications.

Note:
  • The value dddd is the hexadecimal digits sent to the Telnet server when the ATTN key is pressed. For example, if you want the Telnet command IAC BREAK sent to the server, then use the following value: FFF3.
  • The parameter name is case sensitive; the parameter value is not.
  • Spaces must not be inserted between the hexadecimal digits, or between the equal sign and either the parameter name or parameter value.
  • The hexadecimal value specified must be a valid sequence of one or more Telnet commands.
  • The ATTN key override value is only applicable if the session is connected in basic TN3270 mode, regardless of the session's TN3270E property setting. If the session is connected in TN3270E mode then the ATTN key value of FFF4 (IAC, Interrupt Process) is always sent to the Telnet server.
Are you waiting a long time for the cached client to download on OS/2?

When using the cached client on OS/2 with Netscape Communicator V4.61, you must wait for the download complete prompt before restarting the browser. It may take a few minutes for you to receive the prompt, however, this allows the cached client to finish any updates completely.

Are you unable to select the saved file list when using file transfer under Netscape 4.x in Red Flag Linux 3.0?

When you load a file transfer list under Netscape 4.x in Red Flag Linux 3.0, the list sometimes does not display. Try upgrading to Netscape Version 6.

Did resizing your Netscape 4.x browser on a Linux client cause you to log off HODAdmin?

With Netscape 4.x on a Linux client, you may not be able to resize the Administration window when you are configuring Host On-Demand. If you resize the Administration window, you may either be logged off the Host On-Demand server, or you will see the following message in the browser:

Your browser does not have JavaScript support or the support is not enabled.
Try upgrading your browser.

Is the Host On-Demand Service Manager unable to use LDAP?

If you run JDK 1.1.8 on AIX and use an LDAP Directory to store Host On-Demand configuration data, you need to disable a JIT optimization that can prevent the Host On-Demand Service Manager from using LDAP. To disable the JIT optimization, set the following environment variables:

Are there exceptions in the Java Console after you refresh the screen using Netscape Version 6?

When you load an enabled session by refreshing the browser screen or using Action > Refresh in Netscape 6, you will find the following exceptions in the Java Console. You can ignore the exceptions.

Exception occurred during event dispatching:
java.lang.NullPointerException: null pData
    at sun.awt.windows.WInputMethod.handleNativeIMEEvent(Native Method)
    at sun.awt.windows.WInputMethod.dispatchEvent(Unknown Source)
    at sun.awt.im.InputContext.dispatchEvent(Unknown Source)
    at sun.awt.im.InputMethodContext.dispatchEvent(Unknown Source)
    at java.awt.Component.dispatchEventImpl(Unknown Source)
    at java.awt.Container.dispatchEventImpl(Unknown Source)
    at java.awt.Component.dispatchEvent(Unknown Source)
    at java.awt.EventQueue.dispatchEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpOneEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.run(Unknown Source) 
Did Host On-Demand stop working after installing WebSphere Studio Application Developer - Integrated Edition?

During the installation of WebSphere Studio Application Developer - Integrated Edition (WSAD-IE) (formerly VisualAge(R) for Java), WSAD-IE sets the global environment's CLASSPATH to include the Host On-Demand J2EE connector. This connector has a version of the Host On-Demand code that is common to the Host On-Demand clients. In Netscape 4.x and Internet Explorer 5.x, the browser always loads Java classes from the system CLASSPATH before the network. This means that when WSAD-IE is installed, the browser loads some classes from the connector before loading the correct version of the class from the network.

During WSAD-IE installation, the Windows CLASSPATH is updated to include the following directories:

x:\IBM Connectors\class
x:\IBMVJava\eab\runtime30 

These directories contain .jar files with classes that conflict with Host On-Demand classes. Most users do not need these directories in the classpath because they are used only for Java applications that use WSAD-IE's Host On-Demand connectors.

If Host On-Demand does not work after you install WSAD-IE, try the following workarounds:

Are you not able to enter your user ID or password on client login panel?

If you cannot enter user IDs and passwords on the login panel of the Host On-Demand client, try either using the IBM JRE version 1.3 plug-in or clicking out of the field and onto the desktop and then back into the field.

Did you encounter a gray screen when clicking the Users/Groups task on the cached administration client?

Using the cached administration client with Start Session enabled, you may encounter a grey screen when clicking on the Users/Groups task. If this occurs, try upgrading your Java 2 plug-in to the latest service level.

Did a customer-supplied applet fail to run with a Java 2-enabled browser?

If a user runs a customer-supplied applet (that is, an applet written by your company or a third party) with a session (such as 3270 Display) launched from a Java 2 Host On-Demand client, and if this applet requires any Java 2 permissions, then one of the following actions must be taken to meet the security requirements of Java 2, otherwise the applet will silently fail:

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