Accessed Denied to Save Modified Offline Files

Here's an interesting one. Employee at work is running windows 7 on his laptop. We're on a multi domain environment. His location, he employs a Buffalo NAS for all of his documents. He has the NAS sync his folder to his laptop, and has chosen to make the folder available for offline use. That way when he goes home at night, and isn't connected to the network he can still access his files.

Now he runs into problems when he's at home, and say he accesses Document A in his offline folder. He makes changes to Document A, and tries to save. Simple Error message given that access is denied to do so. Items sync correctly, he just can't save anything. I haven't had much time to investigte it (I doubt he's got all of his files set to read only), but does anyone have any insight? I don't have W7 machine handy at work I can test, but I was able to modify my documents in my offline folder on XP and save them no troubles....

Turns out someone selected to do sync'ing with mr Trash can