I had the same problem, although there's only one account on my PC, so not sure if this applies in your case.This error is caused if you move the Shortcuts created by NAV on the Start/Programs menu when it installs in the first instance. Just checkon your wifes' account to make sure they're where they should be. Hope this helps.
With my vain attempt to keep my start/program menu tidy I had similar problems to UncleBulgaria. In an attempt to fix the error message I had a look at the Symantec website and found they wanted £18.00 to try to sort the problem out on a one to one basis. Not willing to "pay the price", in desperation I tried PC Advisor helpdesk and came up with larry48's response. I moved the shortcut back to the start/programs menu and "hey presto" the error message disappeared. Thanks very much for your help Larry48
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