When you have user that needs to access the Reports folder in the Team Project in Team Explorer in Visual Studio 2010 and they can’t because there is a red X on the green icon beside Reports, then set the permissions in the Sharepoint portal.
From the Team Explorer in Visual Studio 2010, right-click on the Team Project and select Show Project Portal. Select the Reports link on the left hand side. This should bring up the reporting services page in your browser.
Now there are two parts to this process. First you need to go into Site Settings and then Folder Settings.
In Site Settings select the Security tab and then click on New Role Assignment, enter the group name or user name and check off System User and click on the Ok button.
In Folder Settings, click on New Role Assignment, enter the group name or user name and check off the roles that you want to enable such as Browser, Content Manager etc. You may check multiple roles. Click on the Ok button to complete.