Question Best way to verify backup files

[SmurfRecorder]

Hello. Which is the best way to verify files (checksums?) when copy

I must copy over 100gb through USB, and last time I was transferring such many gigabytes, some files (jpg) was broken. File size was OK, thumbnails OK, but they displays only partially, while original files was OK.

Is FreeFileSync OK for this task?

I set:
VerifyCopiedFiles Enabled to true
in AppData\Roaming\FreeFileSync\GlobalSettings.xml

 

[USAFRet]

RoboCopy is a good tool.

Also, it might be a fault with the USB or target drive.

 

[Grobe]

You use Windows ?

Suggest you find some file sync tool for such a job. One Windows app I've used for many years is TreeComp, it gives the user very good manual control over files that is changed in one directory, and you can also choose to set up for binary comparison of file contents (can potentially take very long time).

 

[LovelySandriana]

However, I see Teracopy pro and Beyond Compare are exactly what you need in your case, GsRichcopy360 never fail with me in such a situation if I need to be sure that the source is exactly the destination, I use a feature called "byte-level replication", this option should compare the source and the destination, and ensure that both are the same by transferring every change happens in the source to the destination.
For example, if you have the source text and destination text, both contains (a, b, c), then the source text is updated to (a, b, c, d), after running the " byte-level replication ", (d) only will be transferred to the destination text, not the whole text file, and it should be similar to the source text file(a, b, c, d).
So what I am suggesting using this tool, is to mirror the source to the destination the run the " byte-level replication" feature.
That is what I do if I need to be sure that the transfer is correct,
Also, I think all these tools have nice-looking logs that should inform you if there is any failure.