Just an FYI. If you are upgrading to WF5 and using Windchill 9.1, make sure your users upload and clear their cache first. If the local workspace/cache folder is rather large, say over 3gb, WF5 may get a "can not connect to server" error and the only way to fix it is to delete the local cache folder and re-register the WC server. You can reload WF4 and it will connect again to save/rescue any local work the user may have.
If you get the error and want to do a quick check before reloading, rename the local cache folder, start ProE and re-register the server. If it connects the problem is with the local cache. Now the decision - delete or reload...
