I have a main computer, and a laptop that has all my data backed up onto it. In the evening, I hook the laptop up to the home network and back up files I've changed during the day. This was no problem when both systems had Win2000. Now that my big box is running XP, I hit a snag.

I delete a folder from my laptop, then copy that same folder over from my main computer (this ensures an exact copy). I have yet a third Retrospect drive backup hooked into the main computer, but that's extra.

This takes time, but works. Lately, I hit an error message, paraphrasing: "Cannot copy file, may be in use by another application." This wouldn't be too bad, but the copy process can't just skip over it, it stops the whole process, and I'm left not knowing how many files got backed up and how many didn't.

If this were a whole folder, or a drive doing this, I would figure it was some permissions hangup, and work on that, but it's like one or two files out of a whole folder, usually some jpg or graphic file (so far). All the other files in the same folder have no problems copying smoothly except these few, and they are files I haven't used in months, not things I've pulled up recently.

If I try to load the file into Photoshop on my laptop over the network, it comes up a blank sheet of paper. It loads normally into Photoshop on the main machine. I don't know how to ask a file what application is "using" it, or where you can go to examine the "in use" flag setting.

This is cramping my style. Anybody have any ideas?