After several years of satisfied service, the program suddenly stopped working. After repeated appeals to support and patient expectation for about half a year for finding the solution for my problem, I finally got a reply from the support that this is my problem with my Windows operating system. So I left with not working sync program on my own. Such an awful support person I didn't face before, and I hope I will not suffer it anymore. I also think I will have to give up on this program and will try to find another syncing program or use FreeFileSync, as somebody mentioned before.