UDP connection by lsass.exe

Earlier today, when I was just reading a web page on a trusted site, the firewall told me that lsass.exe was attempting a UDP connection via port 500, I blocked it, log below. I was wondering if anyone knew what it was trying to do.

Date/time: 4/16/2009 10:22:44 AM
Application: \Device\HarddiskVolume2\WINDOWS\system32\lsass.exe
Action: Blocked
Source IP: 500
Destination IP: xx.xxx.xxx.xx
Port: 500
Protocol: UDP

Welcome to the Forum, res2216firestar

It is a valid file and should not be blocked. Please see this link.

Ah, I see. One more question since I tend to freak out about duplicate processes: there are 2 lsass.exes running on my PC now, one in /system32 and one in /windows. The /windows has not connected yet, but is it supposed to be there?

Lsass.exe should only be hanging out in /system 32.

Ok, running a virus scan, thanks.