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#21
Preferably you use Seatools for DOS. If problems arise with that one you can use the one for Windows. Obviously for DOS you'll need to have a blank DVD/USB drive or something at the ready to burn it onto so you can start up the PC with it.
As for the dump file itself, right click it and go to Properties, then go to Permissions. Make sure that the permissions are set right. You may need to click the Advanced button and then change the owner to you.
My only other recommendation is to use another archival program to see if that works. Given you're working with rar, perhaps use 7z instead and test that. If that doesn't work, then I have to assume that you have a hard drive problem or something wrong with the filesystem.