BirdieSync

I´m using a Desktop at work and a netbook at home to sync with my HTC Touch2. Both computers are running under XP, the phone under WM 6.5. Since (about) three weeks, at work I get from birdie sync failure messages, that Birdie sync didn´t initialize properly on TB. Currently in use: TB 3.1.2 and BS 2.1.0.1. on both computers; sync with my netbook works like a charm, with my Desktop at work no longer at all! I did already de- and reinstall TB and BS, but to no avail. Connection between Desktop and Phone is flawless, as ActiceSync and mymobiler are still working. Is it a license problem, that I can only sync one PC with one device?