Allocation problems

Symptoms
WebSphere MQ issues the following message:
CSQJ103E +CSQ1 LOG ALLOCATION ERROR DSNAME=dsname,
           ERROR STATUS=eeeeiiii, SMS REASON CODE=sss

z/OS dynamic allocation provides the ERROR STATUS. If the allocation was for off-load processing, the following message is also displayed:

CSQJ115E +CSQ1 OFFLOAD FAILED, COULD NOT ALLOCATE AN ARCHIVE
           DATA SET
System action
The following actions take place:
System programmer action
None.
Operator action
Check the allocation error code for the cause of the problem, and correct it. Ensure that drives are available, and either restart or wait for the off-load to be retried. Be careful if a DFP/DFSMS ACS user-exit filter has been written for an archive log data set, because this can cause a device allocation error when the queue manager tries to read the archive log data set.