Does http://answers.google.com/answers/threadview/id/170482.html help?
Same solution in http://forums.techguy.org/business-applications/409236-solved-locked-editing-error-excel.html
Worth a try, it seems. It may be a hidden file, so have a good look!
Kees
At the beginning of this month our company went through a network migration where all the workstations' names were changed, but the fileserver name remained the same. Now I'm having trouble with 1 particular spreadsheet that resides on the fileserver. When anyone goes to open it, it says 'File in use. File.xls is locked for editing by'___'. It only allows for us to open it as read only or notify when it's available...of course it doesn't notify anyone because it's perpetually locked!
I've tried copying the file onto the same server and renaming it, but when I change data and save, it now shows that the file is locked by me. I've done everything short of opening a blank new spreadsheet and copying all the data over manually (mainly because it's a huge spreadsheet). I've rebooted the server, I've checked under open files in computer management; the file is not listed. I've used the famous "unlocker" program, but to no avail. I've also tried saving a copy directly to my desktop and re-saving it: it works on my local system, but if I upload it back to the server it still says that I have it locked for editing. Any suggestions?

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