Let's Talk about .. MOSS2007&Reporting Service-Error The request failed with HTTP status 401 : Unauthorized

After I managed integration settings and granted database access, I clicked at Set server defaults in Reporting Services of Application Management. Then, I got an error page "An unexpected error occured while connection to the report server. Verify that the report server is available and configured for SharePoint integrated mode. -> Server was unable to process request. ---> The request failed with HTTP status 401 : Unauthorized" as shown in the figure.

After I managed integration settings and granted database access, I clicked at Set server defaults in Reporting Services of Application Management. Then, I got an error page "An unexpected error occured while connection to the report server. Verify that the report server is available and configured for SharePoint integrated mode. -> Server was unable to process request. ---> The request failed with HTTP status 401 : Unauthorized" as shown in the figure.
We discussed and connected live meeting with a support engineer from Microsoft. He said that the cause was the authentication mode of ReportServer host website. The way he used to solve this problem was running the command

[CMD]

cd c:\Inetpub\Adminscriptscscript adsutil.vbs set w3svc\c:\Inetpub\Adminscrpts cscript
cd C:\Inetpub\Adminscripts cscript adsutil.vbs set w3svc/XXXXXXXXX/root/NTAuthenticationProviders "NTLM“cscript adsutil.vbs set w3svc/XXXXXXXXX/NTAuthenticationProviders "NTLM"

where XXXXXXXXX is the identifier of the ReportServer host website.