Question : Problem with OWA since installing Service Pack on Exchange 2003 Server

Since upgrading our SBS 2003 Server to Exchange Server SP1 and then SP2 we have lost the ability to log in via Outlook Web Access, either locally or from outside, even with the full domain name.

I get a reply:

You could not be logged on to Outlook Web Access. Make sure your domain\user name and password are correct, and then try again.

On the plus side, the service packs have sorted some more serious problems we were having.

Anyway, I've tried downloading the KB843539 patch but this tells me we do not have Sp1 installed. I realise this is intended to resolve a problem with Sp1, but it was the nearest solution I could find.

Answer : Problem with OWA since installing Service Pack on Exchange 2003 Server

Also please check the KB293386 at http://support.microsoft.com

2006-10-31 15:37:47 10.0.0.100 GET /exchange - 443 annakeene 81.149.143.41 Mozilla/4.0+(compatible;+MSIE+6.0;+Windows+NT+5.1;+SV1;+.NET+CLR+1.1.4322;+.NET+CLR+2.0.50727) 401 1 1326

the 401 is the authetication failed.  also please ensured that users have OWA enabled, under their Users Property in AD.
also i see the that the user name is being passed using basic authentication,  not domain\username, also make sure the domain name is listed in the domain list under Authentication access control.

The /Exchange Virtual Diectory and default Website should be set to use basic authentication, also stop and start the Default Website if you make any changes.  lots of folks day is not necesary, but I found that permissions do required it.
also check the permission for :  /exchweb/bin/auth/owaauth.dll down to the file it self.
also check this KB903942