The same happens to me occasionally when I connect my external USB hard drive.
What I found;
1] When I see the message, click OK to get rid of it, then immediately try again. This often works.
2] That method didn't work once. I checked for running processes and couldn't find anything relevant, until I check my anti-virus scanner. It was set to scan all removable drives and although I couldn't tell it was scanning this drive at that particular time, I disabled that option, waited a while, then tried the "Safely remove option". That worked.
Mark
I tried to use the "Remove USB Device" tool to safely extract a jump drive. I got a message saying that it couldn't be removed because it was in use. Also, the message said to close any program that was using the device. However, there were no programs running, and Windows Explorer was closed, too.
Two questions: If I am sure that the device is no longer being addressed (no lights blinking), can I just remove it without harm? Also, is there a way to tell WHICH program the computer thinks is using the device?
HP Pavilion, 2.5 GHz, Athlon quad four, 6 GB RAM, 500 GB Drive. Sixth day of trying to get up and running with Win 7.
Thanks

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