Quote Originally Posted by Gallo
Quote Originally Posted by Ughmahedhurtz
ARe you running a software firewall by chance?
I only run a software firewall on my main rig (ZoneAlarm). The others I do not.

Edit: Actually, Windows Firewall is set to On, for all of my 3 problem computers... think that I should disable that?
The ONLY reason I mention this is that software firewalls require CPU and system resources to process network data. If your WoW is running on old/low-spec hardware, it may be sucking up so many resources that software firewalls will start choking and strangle your WoW data pipeline, which will probably exhibit itself as lag, getting out of sync (NPCs/objects missing, invisible mobs, etc.) or disconnects.

I had this problem on one box but fixed it completely by setting the WOW.EXE process priority to LOW via ProcessLasso. Try this and see what you get. I doubt it'll solve everything but it may just make things bearable.