Enable Multi check out files at TFS

Question

I use TFS 2010 with a small team. The policy of check out files does not enable multi check out. But I want that for specific files (only for two files (cs files)) there is

Answer 1

Multiple checkout in TFS can only be enabled or disabled at the project level. To enable or disable it, someone with Team Project Administrator access needs to use Team Explorer to navigate to:

(project) -> Team Project Settings -> Source Control -> Checkout Settings and toggle on the "Allow Multiple Check-Outs" box.

If multiple checkouts are enabled for a project, and you right-click on a specific item in Source Control explorer and "Check Out For Edit", you should now get the prompt asking what kind of lock type to apply. This allows you to specifically do exclusive checkouts on a per-item basis.

However, AFAIK, you cannot limit multiple checkouts to a subset of items, unless you force your users to manually do exclusive check-outs of everything else.

Answer 2

As Mike Edenfield sayd you can enable Multiple Check-Outs in the Team Project Settings :
(project) -> Team Project Settings -> Source Control -> Checkout Settings and toggle on the "Allow Multiple Check-Outs" box.
But it's not enougth:
In (project) -> Team Project Collection Settings -> Source Control, for each file type you want, enable merging, else TFS will lock the file on checkout.