This is happening to 2 seperate boxes.
Both SBS 2003 Std, all patched up to date.
Both are not heavy users of OWA, so we're not even sure when this stopped working. But it WAS working, and nothing has been deliberately changed since.
I have tried resetting the IIS directories, this didnt help. I also compared IIS Permissions to a known working Windows 2003 Exchange Server, and they are identical.
You get the login prompt before this shows up - once credentials are entered you get the error message.
Not using SSL. Yes I know, but they really insist.
Outlook works fine otherwise. Cant see anything suspicious in the eventlog.
ESM has trouble expanding Public Folders too, with the error:
The HTTP Service used by Public Folders is not available , possible cause are that Public Stores are not mounted and the Information Store is not running.
Any ideas? I'm out.