Workgroup PC as peer to peer? There are a number of things that could be causing this. The file shares may not be set up correctly for everyone. Secondly, at a given point it is also possible that they are being scanned for Viruses / Malware by multiple people. Even though no one is using them, this will cause file locking. Even though everyone say’s that they are not using them, it is also possible that someone’s Word or Excel has not released it properly. Remember, that you are not actually opening the file, you are opening a temporary copy of the file. Until that Temporary copy of the file is released the original may also still be locked. This occurs a lot on a peer to peer network. This issue also will occur when you have a flash drive inserted in a USB drive, and the system will not release it because it says that it is in use (scanning for viruses / malware).