As soon as I installed v121 (and later v122) I would get the following error mssg when I tried to open the program:

Version: '1.22 build 260'
Error message: 'HMODULE: 4194304 Unhandled exception EOleException Exception message:The requested resource is in use Call stack: '

Previous version had worked fine, except for the occfassional hang. Cleaning the registry and re-installing didn't help. Luckily, I stumbled accross the fix thanks to a few references here at this forum to firewalls. (I use Tiny Personal Firewall)

The Fix was to go into my firewall settings and delete the two xolox references (in & out). Then when I opened the program, the firewall asked permission to connect. I selected create appropriate rule and don't ask me again, and now xolox is working great! Seems very stable. Hope this helps some of you.

Good luck all! Thanks for a great program, xolox team!