I ran into a problem this month where our WebSphere Windows service account stopped working. This is for our FileNet P8 Environment.
Out of the four WebSphere servers (2 Application Engines and 2 Content Engines), only one server was having a problem. Clearing the JVM Cache did not seem to work. Deleting the WebSphere Windows Service and re-creating the service did not seem to work either.
The problem was resolved after I added the -Xshareclasses:none value inside the “Generic JVM Arguments” field for both the Node Agent and the WAS Server.