Availability Report not working

The Availability Report on the web just stopped working. It created the directory in the "rep", but nothing goes inside it. The webpage redirects to the correct location, but it's empty.

Any ideas on what to look for? Nothing I can see in any of the logs indicates a problem.. Is there any "debug" that can be turned on to figure out why it's not working now? Not sure how long it's been this way, but it has the problem when it try to generate it on the web, it appears to be able to generate it via our daily script, just not via the web anymore.

Thanks.

---Eric