Hi th3bar0n: yes, the support (I think it was denis4inet - see comment above) helped to find the problem and said they will fix it. What happened? I had some files which had a wrong encoding. At some stage I renamed those files on a linux machine and this was the problem. This is how I understood the problem: since the encoding was wrong the old entries in the database were not deleted. But the new entries were added. Thus there were entries for not existing files. What I did to get it fixed: I deleted the whole directory from btsync and added it with a new key. Thus the db was recreated. I did this for all other devices. Btsync still recognized identical files. A complete resync between the devices was not necessary. As I said above I had more than 100G shared on 3 devices. A complete resync would have been annoying but was not necessary. Regards and Good Luck sebneu