I am running McAfee Total Protection 2009 on my Vista Home Premium laptop, which includes version 13 of VirusScan. The laptop is connected to my home wireless network via a Netgear router, which also contains a MyBook World 1TB network drive from Western Digital.
Until recently I have been having a *lot* of trouble moving, renaming and/or deleting files on the MyBook shares. What weeks of troubleshooting have taught me is that the problem has to do with a file locking problem being caused by VirusScan realtime scanning of the MyBook drive; it seems that as soon as I access the file to rename or delete it, VirusScan establishes a lock on the file that, in many cases, does *not* get released, causing a "file in use" error in Vista.
Working with Dell and Western Digital I was able to confirm that my Vista and network settings are correct, as are the permissions on the MyBook drive. I have run several test scenarios designed to confirm (or disprove) that VirusScan is the culprit, and the results point to VirusScan as the problem consistently.
Should anyone reading this purchase a MyBook drive, have McAfee VirusScan installed and experience trouble with "file in use" errors, I strongly suggest you try disabling realtime scanning of network drives to see if this resolves your problem. You will also have to reboot your PC after changing the setting, as once the lock is established, it is only released by rebooting the PC.
I am posting this here because, after several attempts to report my discovery to McAfee through the standard tech support offerings, it seems that all I get is a level-one tech support rep who seems to believe that I *must* be mistaken, and then tries to take me through their standard, choreographed "let's try this, let's try that" process... very frustrating.
Hopefully this post will save someone else from the weeks of troubleshooting it took me to finally discover what was at the root of the problem.