Please see the steps to offer remote assistance in Windows 7\8\Server 2008\Server 2012:
To start unsolicited Remote Assistance, go to command prompt and type msra.exe /offerra. It will open the following wizard:
Type the name or IP address of the machine and click next. This will allow you to connect to the computer without asking for permission to access it.
7. Once allowed, you get the option of sharing screen, chatting and pausing the connection.
I have found that most users are much happier with remote assistance as they can see how you resolved the issue and they also know when you are finished instead of just disconnecting a RDP session and then being unable to get hold of the user again.
The user will also realize quick enough if you don't know what you're doing. Haha!
Hope you find this useful!