Oops, nearly two weeks since a post! That’s a bit of an indicator of how busy I’ve been of late…
Anyway, I had to set up up SQL Server Reporting Services in SharePoint Integrated mode.
Not too difficult on the whole, I’d done it before and found it pretty painless. Just follow the “Configuring Reporting Services for SharePoint 3.0 Integration” article on MSDN and it all just works… last time….
This time I found a few issues, firstly I couldn’t actually access the report server virtual directory by browsing to the url I’d set up for my reporting site using IWA. I was getting a “HTTP Error 401.1 – Unauthorized: Access is denied due to invalid credentials” message 
Luckily I found a great KB article that gave me a workaround.
So next it was on to installing the SharePoint addin and configuring it, no troubles, until I was up to the last step of configuring Reporting Services inside SharePoint where upon I received the “An unexpected error occurred while connecting to the report server. Verify that the report server is available and configured for SharePoint integrated mode. –> The request failed with HTTP status 502: Proxy Error ( Internet Control Message Protocol (ICMP) network is unreachable. For more information about this event, see ISA Server Help. ).” error message 
WTF?? I’m working in a VM environment where ISA is not present, checking my “Internet Options” shows that I’m just using the LAN connection, not using a proxy server and not auto-detecting. Where on earth is this proxy error and mention of ISA coming from?
After some log trawling and interpreting it turns out that SharePoint has a config setting that allows it to auto-detect any proxy-servers…
<system.net>
<defaultProxy>
<proxy autoDetect="true" />
</defaultProxy>
</system.net>
So what was happening was my VM hosted SharePoint instance was detecting our corporate proxy server then trying to route requests for the reporting server through said proxy server which had no idea where my reporting site URL was supposed resolve to.
Toggling the autoDetect element to false solved my issues. I had to repeat this step for the site that was being used surface the reports via the Report Viewer web part.
-Gavin
p.s more posts on the reporting services front to follow 
