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0xc0040017 FWX_E_TCP_NOT_SYN_PACKET_DROPPED - 27.Feb.2008 7:27:44 PM

lachande

Posts: 16
Joined: 8.Jan.2004
From: College of St. Joseph
Status: offline

Hopefully I can explain this correctly.

I've got our ISA setup as the firewall /proxy from our network. Our email server and web page server are on the inside of the ISA.

Our dorms are on a Comcast business connection. The dorms can connect to all sorts of web sites just fine. They only run into trouble when they try to connect to our mail server. I can connect to the mail server from home and other people I know can connect from offsite. This leads me to think that the issue is with the cable modem for the dorms. I had the cable modem replaced. The same issue is popping up.

I looked at the logs for anything relating to the cable modems IP address. I found the following error pop up quite a bit.

0xc0040017 FWX_E_TCP_NOT_SYN_PACKET_DROPPED

Sometimes the dorms can connect to the mail server just fine, then they can't for a bit. After a few hours or so they can connect to the mail server again. I don't think it's the cable modem, I replaced it. That leaves the ISA server.

Is there something I have configured incorrectly? It seems to me like the ISA gets to many connections from the ip of the cable modem and blocks it until there are fewer connections making a request.

To continue, this only seems to happen with our email. It does not seem to do this for our forums, main webpage, or library card catalog.

Does it make any difference if the cable modem uses dhcp to get an address from our ISP. Would it help if I got a static IP?

< Message edited by lachande -- 27.Feb.2008 7:31:21 PM >