User Ping Problem

Sounds like he blocked you by creating an IPsec filter polcy. This link should give you all you need in order to figure out what your problem user did, and enough insight on how you can stop him from playing in the future. http://www.petri.co.il/block_ping_traffic_with_ipsec.htm

he must have blocked all icmp traffic, it can be done with a local firewall. I suggest you should take away all non-job related privileges from the user on local computer.

If the system is XP, you can still get at it with the GPO MMC. Simply go that remote system and see what GPO's are on it. If you see an IPSEC policy blocking PING from your IP address, take a screen shot of the policy and then call your boss and report a security incident.

Frankly, his butt would leave skid marks on the sidewalk if it was me dealing with him...

If he is using xp than he probably has SP2 and has his firewall on not allowing exceptions. If you are on a domain enviroment than you can set the group policy to dissable that firewall or enable it an set some exceptions so he can't change it. Also you can do this on the local machine with gpedit if you are in an work group environment.
http://www.microsoft.com/technet/prodtechnol/winxppro/deploy/depfwset/wfsp2wgp.mspx

How do i set firewall settings in group policies, i havent seen it.

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