There are lots of things that go on in background all the time including Time Machine backups and Spotlight refreshes that create disk activity. When you say
Originally Posted By: slolerner
I did check the log and it is finding several EOF errors that it can't fix on that drive
what is IT? The Log does not find anything but the task reporting the EOF errors should be indicated in the log which should give you an indication of what the extra-curricular task is.

When you ran Disk Utility, what specific function did you ask it to perform? Repair Disk? If it was Repair Disk when DU completed it should have reported what, if any errors were found and whether or not they were repaired. DU is NOT the best volume/file repair utility out there but when it does report errors it could not repair sometimes running it a second or third time can eventually effect repairs. If there are still unfixed errors you are in need of Diskwarrior, TechTool Pro, or Drive Genius. EOF errors are repairable, but you may end up with truncated files in the process.

Last edited by joemikeb; 10/07/14 09:10 PM. Reason: (&$% spell checker

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