Guest account window error message

We have a PhotoShop Elements 11 Volume License running on Win 7 64bit pcs in our Labs. I installed the software under a student account in 2013 and it has been fine until now.As of last week, ;when students try to launch the Photo Editor or the Organizer, the following window message appears: "cannot use the product under a guest account".

Our IT states that no changes have been made to our Lab machines.

When I select "run as administrator" it of course runs fine, but students on their network are unable to run the program.

Can you help me make this software run for our students?

Thanks,

Randy

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