I'm using Nuts & Bolts to try to defrag. I get error messages: "Unable to process. Open unmovable files" and "Process aborted due to excessive disk activity." I've also tried to run ScanDisk. The message I get is: "restarted 10 times because windows or another program has been writing to this drive." I've closed all the programs in the task manager except for systray and explorer, and I still get the same message. How do I find out what program is causing this problem?

Thanks in advance for your help.