Accessing report builder from client machine?

Accessing report builder from client machine in which there is no sql server with the url http://<server name>>/reports. The report builder tab is not getting displayed.

when accessing from http://<server name>/reportserver/reportbuilder/reportbuilder.application it gets connected to the report model but when we are running the report it say the user doesnt have sufficient permissions or database can not be processed.

The permission is given to the user on the data source. For admin permission the report is running fine.

Do anybody know the procedure to run adhoc reports from client machine?

Urgent!!

Not being able to see the Report Button means that the user doesn't have the necessary rights to run Report Builder. The user must have rights to the Execute Report Definitions system task and the Report Builder user role tasks.|||

well, I can see the report builder button from client machine. But When I click on it, I go the following Error.

"Can not retrieve Application. Authentication Error."

I am sure that I have full rights to run report builder. any help will be appreciated.

Thank you