You should also look into anti-virus software. Additionally, if you are using a SAN or NAS, there may be volume replicating servi ces executing. However you can actually delete the file without rebooting - of course you'll need a little help ... the Winternals Process Viewer (it's free !) ... it's just an executable and a help file (no installation or reboot needed) ... it will allow you to look for the process or file handle that has the file and you can then either kill the process or if the process is already dead, close the file handle ... then fou can delete the file.
Senior Database Administrator
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