I recently experienced issues with GFI LanGuard again. I don't know why, for a long time this product was it for me and really enjoyed using it. Lately though it has been a royal pain.
I kept noticing my account was being locked out every ten seconds or so. I immediately suspected LanGuard so I checked the service on the LanGuard machine. The service was under another account I created solely for this program so it wasn't the problem. I also checked DCOMCNFG from the run command and under LNSS, the same account was used. After a while I started to think maybe it wasn't LanGuard but something else. To test this theory I stopped the GFI service and unlocked my account again. I used my account for a good 30 minutes and decided it was GFI causing it because my account was no longer locking out.
After digging around a bit I finally found the problem;
I apparently had my credentials set in one of the folders or the Active Directory like tree. It didn't even have a password, it was just domain\username so it was constantly trying to refresh the status of the clients with this account and locking me out. The unfortunate thing is that LG didn't even bother telling me this issue was occuring. For example when I had ran a "refresh info" scan on all the computers, they just stayed stuck on "pending" and never started. In either case, make sure you check this hierarchy and find if you have any alternative account setup.