We have a site that appears to be losing their connection to their default gateway (which is actually a cisco asa 5500).  They receive DHCP IPs from the firewall.  It happens about a couple of times every day.  I started running wireshark on one of the servers and I’m getting the bad tcp/checksum error quite a few times, usually involving the same destination (a client computer).  I’m not really sure what that means, though.  Should I check that computer for virus’ or spyware.  It should have McAfee on it, though and it is currently on the network, so it would be updated (as long as everything is running correctly).  What do all the bad tcp packets imply?  What else should I be on the lookout for?  Thanks in advance for any help!

Lauren