Action Required window appears on limited accounts

nis 2011

The Action Required window keeps popping up for all users on my computer - admins and limited accounts. i cant stop it for admins, apparently. it says that my thunderbird inbox contains viruses and offers to delete the entire inbox. obviously i dont want that, but the choice norton offers is to delete or cancel. as this pops up on limited accounts also, at some point one of my children is going to click "Apply" (ie delete), deleting my inbox.

obviously this window should not appear for limited accounts and seems to be an error in the programming. how do i stop it appearing for limited accounts please? ideally i want to tell nis to stop offering to delete the inbox, but there is no option to do that - it seems i just have to cancel the window every time i log in to windows.

thanks for any help