I have an Exchange 2007 server with SP2 sitting behing ISA 2006 and all is working fine. OWA is only using basic and windows authentication.
I need to create a 2nd owa website using just basic authentication. I have created the 2nd virtual directory through Power Shell (new-owavirtualdirectory -name owa2 -websitename 2ndsitename) with success and it shows in both Exchange console and IIS. However the first OWA dies with a 500 internal error. The only way to get the first OWA working again is to remove the 2nd OWA virtual directory in Power Shell.