Error - Attempted to perform an unauthorized operation

I’ve faced a problem while trying to deploy a webpart created in Visual Studio 2008 with Sharepoint webparts template. I did the coding and build the project without any problem, but when tried to deploy it using visual studio, Build -> Deploy Solution, it had thrown an error “Attempted to perform an unauthorized operation।”

Reason: The possible problem is that you are trying to deploy solution on a site to which you don't have authorization to deployment.

Solution: Check the URL to which you are deploying the solution, by default it is http://localhost/ , change it to your site where you actually want to deploy the webpart.
Go to the project properties and inside the debug tab select the start action as 'start browser with url' and enter the valid site collection URL।

Though, there may be different reasons of this error because of any other authorization failure, this is also a main reason. Hope this fix might help.