When saving backups, e.g. in Google Drive, the error message may appear:

"Invalid file - Please select a valid file to restore the backup successfully"

In this case, please check whether the .obk file extension was removed during the data transfer - that could be the cause of the problem. If this is the case, simply rename the file and add the ending .obk to the file name.

Make sure that there is no space between the period and the .obk.