Solution: Blank Report Manager (SQL Server 2005 Reporting Services)

If, after installing Reporting Services you see a blank screen when trying to open Report Manager, you can try the below methods to get you moving.

If you have an Administrator account on the local machine:
· Enable Integrated Windows Authentication in the Reports (and ReportServer) virtual directories in IIS, and disable Anonymous Access.
· Restart IIS (iisreset on command line)
· Try to open Report Manager. If your account is recognised as an Administrator, you should see more content in Report Manager.

If you still can't see full content in the Report Manager, then you can try this:
· Add the local anonymous IIS account (IUSR_MACHINENAME) to the Administrators group for the local machine (this is just temporary, read on).
· Restart IIS (iisreset on command line)
· Try to open Report Manager - you should now see full content.
· Go to the Properties tab, and click New Role Assignment. Grant the IUSR_MACHINENAME account the appropriate privileges to access the Report Manager (be careful not to allow too much access since this means your users could change/delete reports).
· Remove the IIS account from the Administrators group for the local machine.
· Enable Anonymous Access for the Reporting Services virtual directories in IIS, and disable Integrated Windows Authentication.
· Restart IIS
· You should now be able to see the appropriate content within Report Manager.

Hope this helps! It worked for me, and I had been going mad with frustration