Can anyone explain this kind of virus to me?
looking through another private collection, I found LOTS of "broken" disks which could be easily fixed in a blink of an eye, so that they work 100% afterwards.
Each disk had a provoked checksum error on Block 2.
(Codetapper, that's the same kind of thing that "infected" the Gridiron disk you cracked months ago).
The "fix" is trivial: just take a disk editor and change the 00000000 ( = nothing) at the beginning of the block to 00000008 (= data block).
There are NO OTHER modifications needed, even the checksum is the same like before, which means that some "routine" must obviously have been programmed to aim directly on block 2 and thus overwrite the data block signature with eight zeroes, whilst leaving every other stuff untouched. After that, the disk works without any further problems.
This must definitely be a common virus, but which?
Last edited by andreas; 17 October 2001 at 15:47.