ISA and TMG give you this error when the TCP connection is broken unexpectedly. If you get a network capture of this process, I'll bet the server or client close the connection before ISA expects it to. Netmon 3<http://www.microsoft.com/downloads/details.aspx?FamilyID=983b941d-06cb-4658-b7f6-3088333d062f> is a great tool for that task. Jim From: isalist-bounce@xxxxxxxxxxxxx [mailto:isalist-bounce@xxxxxxxxxxxxx] On Behalf Of Lars Hansen Sent: Friday, September 04, 2009 10:38 AM To: isalist@xxxxxxxxxxxxx Subject: [isalist] oh no, error 64 - network name no longer available One of our clients are getting this error when they go to one of the website that they have to go to. We've tried the URL through 3 different ISA servers, and we're getting the same error through all three ISA servers. If we test this at sites not using ISA, we are having no issues with this URL. Configuring IE to use ISA as a proxy or not does not appear to make a difference; same error. The actual error message on the firewall is this: Log type: Web Proxy (Forward) Status: 64 The specified network name is no longer available. Rule: Allow all HTTP traffic from ISA Server to all networks (for CRL downloads) Source: Local Host ( 192.168.16.2:0) Destination: External (216-136-16-106.static.twtelecom.net 216.136.16.106:80) Request: GET http://www.refil.net/xap/refil/invlib/?customernumber=[redacted] Filter information: Req ID: 174477d2 Protocol: http So, here's the "funny" part. If I try http://www.refil.net/xap.refil/invlib, I get the correct login screen without any issues. However, once the URL gets filled up with user ID information, it fails: http://www.refil.net/xap/refil/invlib/?customernumber=99999&from=liebert&userid=99999-S&repnbr=999 (actual userids and customer numbers changed, still get the same error) I tried creating a special rule to pass everything going to refill.net through a special port-80 protocol without web filtering on it, but still no go. Also, the rule listed in the error message doesn't show on the firewall, so I can't edit and/or disable it. Even with a custom rule, this one always picks it up and throws the error. During my google & bing searches, I noticed another gentleman had a similar issue, and someone pointed out the odd use of "/?", and then he rewrote the app to use something else eliminating the "/?" and the issue went away. However, it works with /?customernumber=99999 as well as /?customernumber=99999&from=liebert, but when the URL grows bigger than that, ISA barfs all over it and suddenly throws the "error 64" message. Any ideas? Sincerely, Lars M. Hansen Engineer II MicroData Group, Inc. 100 Cummings Center, Suite 146N Beverly, MA 01915 Voice 978.921.0990 Fax 978.921.0950 http://www.microdata.com<http://www.microdata.com/> [cid:image001.jpg@01CA2D7E.109D1660]