Backup succesfully done but no .TIB files on target

Using backup server and workstation last version 8206 (I tried one before also), I can do the backup succesfully (at least is what log says) but when look at target folder there are no .tib files, there are many files of 2.097.152Kb with no extension an named with numbers and letters like this:
0E29E76F-5E0F-4D1D-8163-0A3049E3BD47
D89C8D75-1C93-45C9-95AA-A38EDDBB2861
0327AB18-1089-4982-94B5-77DC23443A76
82EEEC4-C57A-4093-B95B-46FBBD3CEE11E
etc....
I even can see in Backup Archives (from ATI management console) that there is a backup.
Where is the tib file!! I have repeated the operation many times and I get the same result.

 

I think this is normal for Backup Server (see this post by Acronis Support).