I cannot edit any files (checkout error or user cancellation)

I am trying to work on a new project, which is accessed through Team Foundation Server 2008. I don't have any experience in working with tfs, but it seems pretty straight forward what to do. Here is what I did:

1) Tools -> Connect to Team Foundation Server...

2) Select the project, then OK.

3) In Source Control Explorer, I right-click and select "Get specific version..." and choose "Overwrite all files even if the local version match开发者_运维知识库es the specified version", then "Get"

4) Then it asks "Projects have been added to this solution. Do you want to get them from source control?" and I select "Yes".

5) Then there is an error. "Unable to read the project file '...CommonLogic.DocumentUtile.csproj. 'D:...CommonLogic.DocumentUtil.csproj' was not found. I click OK.

6) the project "CommonLogic.DocumentUtils" is now unavailable in the Solution Explorer. It says "The project file cannot be loaded."

Anyway, I don't know if that error is the cause. But when I try to edit any file in the solution (not in the above project), then I get a popup that says: "Checkout error or user cancellation" and a text of the current file stating "File was not checked out".

What is the cause of this? and what can I do about it?

This error will occur when you don't have permissions to the file.