I create backintime backups to a local USB disk. My customer wants me to remove his confidential files from my computer and my backups. Can I just delete folders inside the backintime folder hierarchy without affecting the rest of the backup?

It is especially the file fileinfo.bz2 that is worrying me because it contains information about files that will have disappeared when I manually delete them.

And yes - I know that backintime uses hard links, so in principle I would need to repeat the delete for more backups, but fortunately, the confidential files only occur in the most recent backup.

Is it feasible to take a new snapshot excluding the sensitive files, then delete them from previous snapshots using the Snapshots Dialog?

Yes, that might be an option, but I would prefer to keep the snapshot, with only the sensitive files removed. My guts feeling is that deleting files would do no harm, but I would like to know if anyone has a different experience.

Oooh... I just found out that I can browse the snapshots and navigate to the folder that I want to remove. Then right-click and select "snapshots". Then you can delete files.... so yes, that will be the answer. I'll report after trying it out and then close this thread. Thanks a lot!

I confirm that shruggy's solution works. Here's again how to do it:
- In backintime, navigate to the backup and then the folder that you want to delete from the backup
- Right-click on the file or folder that you want to delete
- Choose snapshots
- Check if the right file or folder is listed in the top of the dialog
- Click on the red cross icon to delete

Afterwards, I checked if the files were really gone. They were.
I also noted that the file still has its original date, so that is probably not modified. Apparently, that does no harm.