Just in case anyone is a TFS 2010 user, and they don’t like the multiple checkout support that it has (i.e. more than one person can edit the same file, and they just have to resolve conflicts on check in) then you can change it to use the old-school approach of full locking on checkout – this means that only one person can edit a file, or even, hold a lock on it. If anyone else wants to edit that file, they are blocked until you check in your changes.

Why would you do this? Well, pretty much the only reason is if you have developers on your team who don’t understand “current” source control and you keep loosing changes when people check in.

So, how do you change this option? It’s easy enough, but you will need permissions on the Team Project to change it – if you are unsure, speak to your TFS Administrator.
To get to the option itself, first go into Visual Studio, to the Team Explorer and then right click on the project you want to change the option for. Then select Team Project Settings, then select Source Control.
In the dialog that appears, untick “Enable multiple check-out” and hit ok.

Job done.