External hard drive corrupting ISOs

I have an odd problem. I have a few backup iso files for some games on my external. I havent played them for a while but it seems like when i transferred the game from my computer to the external it corrupted the iso somehow. All the iso files give me a data cab corruption error and cannot install the game. Whats going on?
How can i prevent this in the future?

 

Yes, it is very possible that the data was corrupted some how.

The problem is most likely caused by a problem with:
(1) The original ISO files themselves. You test this by creating an ISO, and then testing to see if you can successfully read / extract it;

(2) The hard drive itself. You test this by running a series of scandisk tests, disk health checks, etc to see if there are any bad sectors on the disk or errors on the disk. It is best to remove the drive from the external enclosure, plugging the drive into a desktop computer, and running your tests from there (just in case it is the enclosure that is the problem).

(3) The external hard drive enclosure. You test this by putting a known-good hard drive into the enclosure, and copy / restoring ISOs to see if there is any data corruption.


If the problem is #1, then you prevent this in the future by testing the ISO you created before copying to an external drive. If the problem is #2 or #3, you prevent this in the future by testing the ISO after you copy to an external drive.

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