Since you mentioned use of a roaming profile, I just want to make sure you're not expecting Protect on different systems to have access to the same credentials.
Do you have a screenshot of the actual error? More than likely we will need to take a look at the logs from Protect to see what might be causing this. If you want you can PM me the logs or open a case directly with support to work more closely on this issue.
Here are the best steps to use for obtaining the Protect logs:
-In Protect go to Tools > Options > Logging and make sure both User Interface and Services are set to “All”. Save.
-Stop all the Shavlik (VMware vCenter Protect) services.
-Delete all the logs from:
-Vista, 2008, & Win7: C:ProgramDataShavlik TechnologiesLogs
-Windows XP & 2003: C:Documents and SettingsAll UsersApplication DataShavlik TechnologiesLogs
(These may be in a VMware directory rather than Shavlik Technologies for v.8.0 and above.)
-Start the Shavlik (VMware vCenter Protect) services and open Protect.
-Reproduce the error/issue.
-Afterwards please zip and send all the logs.