You can remove a repository from your repository list in the Asset Explorer view so that it is no longer accessible; however, you cannot remove pre-installed repositories like the Patterns.
To temporarily block access (refreshing and searching) of the repository, you can close it. Closing a repository instead of removing it retains the connection information. You can easily change the mode back to open and view the repository's contents or include it in a RAS asset search.
Before you delete a repository, you should record the address connection information so that you can reconnect to this repository again. You can view this information in the Asset Explorer view by right-clicking the repository's node and then clicking Show Properties View.
To delete a repository connection: