Corrupt file needed for testing

[ThomasB]

Hello,

I use Folder Compare to check backups for integrity. I use SyncBackSE for doing the backups.
I would like to do a test to see if Folder Compare correctly identifies a corrupt file, compared to the same but not-corrupt one. The problem is that I don't have any corrupt file.

It would be nice if somebody could send me two versions of a file, one which is corrupt (i.e. slightly changed), the other not. I think that file name, date, time, and size, should be the same for both files.
If you have such files, please send them to me inside a ZIP archive, containing two folders with one file inside each of them.
Or is there a way to change date and time of a file? This way I could set them as the same for two different files.

My address is: tbecker76(AT)tin.it

Actually I have already done a kind of "simulated" corrupt-file comparison.
I put two identical text files inside two folders; I loaded the folders inside Folder Compare, and the program correctly identified them to be the same by date, time, and size (without any kind of in-depth comparison).
Then (without touching anyting in Folder Compare) I changed just one character inside one of the text files (this procedure changes also date and time of the file), and run a binary comparison.
Folder Compare correctly identified the two files as different, while continuing to display the previous date and time (before doing the change).
This indicates that regardless of two files having same date and time (and name) -- as far as I understand a corrupt file should have same date and time, but slightly different contents -- Folder Compare correctly identifies the differences when doing a binary compare.

I think that this should be enough (do you agree?), but I would like to do a test with a real corrupt file, all the same.

[Aaron]

Hello,

Running a binary scan on two base folders and the files within would be a good method of determining if they are different in any way.

You can create two files of equal size in notepad, and alter timestamps using the BC3 Touch command. This is a good test of detecting differences, but it isn't a real "corrupt" pair of files.

Just be aware that the default scan for BC3 is only timestamp and size. If you wish to always run a binary scan, you'll want to update the session defaults on the Home screen -> Edit Session Defaults folder -> select Folder Compare -> Comparison tab: enable binary (and leave the other options enabled and on the defaults).

[ThomasB]

Thanks, I did the test with the Touch command, and everything worked as it should. When initially loading the directory contents, the two files got identified as same (with black text), and after doing a binary scan, they got correctly identified as different.

What would be the difference when doing the test with a real corrupt file? Shouldn't it work exactly the same? Isn't a corrupt file just a file with same timestamp (and size?), but with slightly different contents?

[Aaron]

You can configure BC3 to always perform the binary scan. That way you don't have to run two comparisons, or have it return less accurate results the first time.

And yes, a binary scan should catch cases of corrupted files that still have the same file size.