OWA on Exchange 2003

I just installed Exchange in a single server enviroment, no Fe/BE on W2k server. By default OWA should work, it doesn’t. I get a ” Server Application Error” when I try to access the logon page. I believe it to be something with IIS 5. The virtual web-site seems to be set up correctly.

Any ideas on troubleshooting would be appreciated.

Thanks.