Looking at the logs some more, there are more differences than I thought... Here are two of the entries... The first one is when trying to go to cnn.com; the second is going to cnn.com after restarting IE. Original Client IP Client Agent Authenticated Client Service Server Name Referring Server Destination Host Name Transport MIME Type Object Source Source Proxy Destination Proxy Bidirectional Client Host Name Network Interface Raw IP Header Raw Payload Source Port Processing Time Bytes Sent Bytes Received Result Code HTTP Status Code Cache Information Error Information Log Record Type Log Time Destination IP Destination Port Protocol Action Rule Client IP Client Username Source Network Destination Network HTTP Method URL Filter Information 0.0.0.0 iexplore.exe:3:5.1 GATEWAY - TCP - 3866 0 0 0 0x800733f5 0x0 0x0 Firewall 10/2/2006 12:48:38 PM 64.236.16.84 80 TCP 80 Block Denied Connection Non-Proxy Web Block Rule 10.20.4.236 MAPSNET\dball Internal - LAN Network External - - - 0.0.0.0 Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; MAPSIE; .NET CLR 1.1.4322; .NET CLR 2.0.50727; InfoPath.1; MAPSIE; MAPSIE) Yes Proxy GATEWAY www.cnn.com TCP Internet - - - - - - 0 750 46205 3019 200 0x41620000 0x480 Web Proxy Filter 10/2/2006 12:48:56 PM 64.236.16.84 80 http Allowed Connection Web Access 10.20.4.236 MAPSNET\username Internal - LAN Network External GET http://www.cnn.com/ ________________________________ From: isalist-bounce@xxxxxxxxxxxxx [mailto:isalist-bounce@xxxxxxxxxxxxx] On Behalf Of Ball, Dan Sent: Monday, October 02, 2006 1:01 PM To: isalist@xxxxxxxxxxxxx Subject: [isalist] Re: IE Problems? Just ran into the problem again on my computer. Checked the logs, and it is properly authenticating, resolving the DNS name, everything looks good except it is trying to use the normal Port 80 instead of using the proxy. Next time it happens I'll try the autoconfig URL and see if that clears it up. ________________________________ From: isalist-bounce@xxxxxxxxxxxxx [mailto:isalist-bounce@xxxxxxxxxxxxx] On Behalf Of Ball, Dan Sent: Monday, October 02, 2006 12:34 PM To: isalist@xxxxxxxxxxxxx Subject: [isalist] Re: IE Problems? Nope, that is disabled. ________________________________ From: isalist-bounce@xxxxxxxxxxxxx [mailto:isalist-bounce@xxxxxxxxxxxxx] On Behalf Of Wayne Berry Sent: Monday, October 02, 2006 11:44 AM To: isalist@xxxxxxxxxxxxx Subject: [isalist] Re: IE Problems? Are you running the ISA SP 2 Compression? -Wayne ________________________________ From: isalist-bounce@xxxxxxxxxxxxx [mailto:isalist-bounce@xxxxxxxxxxxxx] On Behalf Of Ball, Dan Sent: Monday, October 02, 2006 8:21 AM To: isalist@xxxxxxxxxxxxx Subject: [isalist] Re: IE Problems? Yes, that does look like what is happening. I had one a few minutes ago that I started diagnosing, it kept coming up as host not found, then all of a sudden it started working again (before I could finish trouble-shooting). Maybe not an IE-specific problem? Maybe we just notice it more because IE makes more DNS calls than anything else... ________________________________ From: isalist-bounce@xxxxxxxxxxxxx [mailto:isalist-bounce@xxxxxxxxxxxxx] On Behalf Of James May Sent: Monday, October 02, 2006 10:24 AM To: isalist@xxxxxxxxxxxxx Subject: [isalist] Re: IE Problems? Yes,I have see this exact thing, IE acted to me like DNS lookup was failing? I also had php errors on some site which is probably a different issue. Jim ________________________________ From: Ball, Dan [mailto:DBall@xxxxxxxxxxx] Sent: Monday, October 02, 2006 6:55 AM To: isalist@xxxxxxxxxxxxx Subject: [isalist] IE Problems? Anyone else experiencing this lately? Browsing the Internet is working fine, then all of a sudden nothing loads at all... You hit refresh and it sits there for awhile then finally comes up with an ISA-generated error page saying the site is unavailable. You exit IE, re-open it, everything works again... I don't think it is the ISA2004 server, as restarting IE fixes the problem temporarily. I thought it was just an issue with my computer, as I'm running IE7 RC1, but many other people are reporting the same problem now. I've been using my laptop (with all the same software) at home with no problems, so I'm wondering if there is some patch for IE that came out recently that doesn't like proxy servers... Just wondering if anyone else has seen this symptom... Next time I run into it I'll do some more diagnostics.