>in Premiere 7
Do you mean the really OLD Premiere 7 (aka Premiere Pro 1) or do you mean Premiere Elements 7?
Are you working on a network?
If so, are your media and project files stored on the individual computers or on the network?
If on a network, you need to contact Adobe Tech Support. This program has some unique configurations and challenges when not installed a standalone PC.
Premiere Elements 7, sorry.