I run IT for a group of remote users software and hardware, and my coworkers in the net team manage their networks. For the past 2 weeks we have been beating ourselves over an issue that we cant seem to solve.Symptoms:Users cannot visit any HTTPS sites (they all hang after the auth page, and eventually timeout)Users cannot reply to any emails in their inboxUsers cannot attach files larger then several lines of plain text (<10k size)Update.microsoft.com fails after selecting express or custom install, automatic update is still able to pull updates off our SUS serverEquipment Involved:Cisco HardClient VPNCisco Gigabyte 24 port switchGateway E4300 or E4500Software:Windows XP Professional SP2Novell NetworksIE 6/7Outlook 2003 ProNow here is where it gets fun:I can take a linux live recovery CD, boot it on any of these PC's and it will be able to access both the HTTPS sites that dont work, as well as our webmailOne of the non-standard image machines works fine, no issues at allOur network teams gateway laptop with the standard image, works fineA fresh Windows XP Pro SP2 install works fine, BUT! if you install all the microsoft updates, it STOPS working.After going through and adding and removing security updates for a day, we found that if we remove 917953 critical security update, that our test machine works. Reinstalling this patch, brings all the issues back.BUT this fix does not work on any of our standardly imaged machines.The non-standard image also appears to work with or without the patch (it has all the same programs as our standard image, but was compiled from scratch by one of our net team)Any suggestions would be awesome, and yeah, I'm currently trying to get ahold of Cisco to see if they can help-Squadro

We had a similar issue whereby people couldnt authenticate on certain in house webservers, not use the front end email server etc. For us it was a kerberos issue for VPN users although when working on the internal LAN they were fine. http://support.microsoft.com/default.aspx/kb/244474was the resolution for us, you could try it, nothing to lose really as you can always undo it easy enough. PS this is the Exchange forums