I have been tearing my hair out for weeks on a Report Services 2008 problem. The symptoms are that requests to the web service that are made programmatically never seem to get to the RS ReportServer/ReportService2005.asmx web service never seem to get there and the ReportViewer component hangs try to get the reports.
Interestingly, Report Manager works fine which makes me think it doesn't use the web service!
I have tried all sorts of things including turning off the firewall, reinstalling SQL 2008 etc etc. I was astonished to find out that disabling the LinkScanner in AVG was the final solution to the problem... Wht did AVG not tell me it was blocking these requests?????
Bizarre, but problem solved now!