When logging into DM Client, the user gets a DDM20225E error.
ERROR: The library list is not available because it cannot be retrieved
Ask your IBM Document Manager administrator to update the cache by
running Cache Manager.
Internet Explorer is running in Protected Mode and cannot update the cache files on the DM Client computer.
Resolving the problem
In Internet Explorer, go to Tools->Internet Options, select the Security Tab, un-check 'Enable Protected Mode'