There are two KBs I would like for you to see, since they might have the answer to the problem you are having:
1. This KB is related to having access to the TEMP directories where Multisim stores temp files for simulation:
2. This other KB deals with non-Administrator users of Windows, it talks about v9 but the idea is the same for v10, just look for the v10 installation paths:
Thanks Nestor, one of the links you sent has the solution to my problem.
Everything is running fine now.