In order for Visual studio 2010 to connect to a Team Foundation Server 2012 server, you will need to perform the following steps:
1. Download and apply Visual Studio 2010 Service Pack 1
2. Download and install Visual Studio 2010 SP1 Team Foundation Server 2012 Compatibility GDR
To connect to the server, open Visual Studio 2010 and then perform the following steps:
1. From the Team menu, select the "Connect to Team Foundation Server..." option.
2. Click the "Servers..." button.
3. Next, click on the "Add..." button.
4. Supply https://tfsXX.discountasp.net:443/tfs/ for the "Name or URL Team Foundation Server" field where "tfsxx" is the Team Foundation Server 2012 server for your account and then click on the "OK" button.
If you need to find out what server you're hosted on, access the Account Information
page in your Control Panel.
5. At the "Add/Remove Team Foundation Server" screen, click on the "Close" button.
6. Select the projects you have access to and then click on the "Connect" button.
Note: You will not be able to create new Team Projects using Visual Studio 2010. To create a new Team Project, you will need to download and install Team Explorer for Microsoft Visual Studio 2012