After installing SP3 on Exchange, any connection to OWA gives the following result:
EMC may or may not work (it didn’t and then it did for me).
I went to the web.config file located in the snapshot and I realized that I had the line <add name=”exppw” /> added (line 22). When we compared it to another client’s server, the client’s server had the same line but on our server, the line was out. I removed the line and everything worked.
I’m speculating that during the update, the line was added elsewhere or possibly the line was supposed to have been removed elsewhere. Not sure what the ramifications are yet but for now all is good.
Same problem but the error page just displayed HTTP Error: 500 and nothing else. The same solution worked.