I encountered a problem where I could not install Monitoring Server Report Pack. I was running the install from the Monitoring Server against a back-end SQL 2008 server. The error message I got was like this: 

Could not connect to server:
https://server_name.domain.com/reportserver/reportservice2005.asmx
Failure [0xC3EC7A20] Failed to install the QoE Monitoring Server report pack 

I found that there are three possible resolutions: 

1. Make sure you are using https:// for the reportserver URL
2. Check that you are not behind a proxy server
   • Double check that “Automatically detect settings” is not selected under Internet Options->Connections->Lan Settings i IE
3. Add the account that is being used for Office Communications Server 2007 QoE Monitoring Server installation as a system administrator on the SQL Server report server.
   • To do this, follow these steps:
     1. Start Report Manager.
     2. Open Microsoft Internet Explorer 6 or a later version of Internet Explorer.
     3. In the Internet Explorer address bar, type the Report Manager URL. By default, the URL is https://ComputerName/reportserver
     4. Click Site Settings.
     5. Click Configure site wide security.
     6. Click New Role Assignment.
     7. In Group or user, type the account in the following format: domain\account
        • If you are using forms authentication or custom security, specify the user or group account in the format that is correct for your deployment. Assign the System Administrator role to the account, and then click OK to apply changes.
     8. After the account is added to the report server as a system administrator, restart Office Communications Server 2007 QoE Monitoring Server setup to complete the installation. 

The resolution for me was that I was behind a proxy without knowing it. Therefore it is wise to double check proxy settings. 

I have also encountered this error when the reporting services resides on a server with Server 2003. Apparently the max request bytes allowed was set to low to allow OCS to install the report pack. Here is how you resolve that. 

1. Add the following registry key with the following value:
   • Key: HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\HTTP\Parameters
   • Value: DWORD “MaxRequestBytes”
   • set it to 1048576 (1MB). (This number can be raised or lowered depending on the situation)
2. Stop the SRS Windows Service. (SQL Reporting Services Service)
   • From a cmd prompt run “net stop http” then “net start http”
   • You may have to start the www publishing service manually
3. Try the OCS installation again.