This is my scenario: 
Database: SQL Server 10.50 and SSRS 2008 R2 
App: 
I'm doing an ASP.NET application using ReportViewer component. The web app is developed on Visual Studio 2010.
When i try to print the reports using the development server there's no issue. Once i do a deployment on the qa server, enter the site and click over the Print button, and install the active x, a pop up window comes and this error is shown:
An error occurred during printing . (080004005)
For more details on the error:
Message: Unspecified error.
Line: 1012
Char: 13
Code: 0
URI: http://mysite/Reserved.ReportViewerWebControl.axd?OpType=Resource&Version=10.0.30319.1&Name=ViewerScript
I've invested hours on internet but all solutions point to SSRS 2005.
I took a look on C:\Windows\Downloaded Program Files.
My development server (wich runs when i click debug on Visual Studio) installs these files:
RSClientPrint-x86.inf
rsclientprint.dll 
rsclientprint_3082.rll 
rsclientprint_2052.rll 
rsclientprint_1049.rll 
rsclientprint_1046.rll 
rsclientprint_1042.rll 
rsclientprint_1041.rll 
rsclientprint_1040.rll 
rsclientprint_1036.rll 
rsclientprint_1033.rll 
rsclientprint_1031.rll 
rsclientprint_1028.rll 
And works fine. But when i go to the qa site IE asks for installing again the ActiveX. Why happens this if the dev server all ready have done that?
FYI QA Site and Development uses the same SSRS url, their not in different servers.
Any help will be appreciated.
Thanks.