maybe useful for Add the solution to source control

下面这段方法可能对于前两天我所遇到的签入source safe时多了一层folder的情况有所帮助，不过我还没有测试，周一到了公司再去测试下，然后再来发结果出来
How to: Disable Creation of the <solutionname>.root Folder

When you add a solution to source control, your source control plug-in automatically creates an empty <solutionname>.root folder in the database to contain the unified root for the solution. For more information about the unified root, see Introducing Source Control.

Caution:
Disabling automatic creation of the <solutionname>.root folder will change the behavior of your source control plug-in when you add multi-project solutions to source control. For one thing, operations that add projects will take more time. Additionally, you will have to respond to redundant prompts when performing source control operations on multiple projects.

To disable the automatic creation of the <solutionname>.root folder

1. On the Windows desktop, click Start, then Run.

2. Type Regedit, and then click OK.

3. Open HKEY_CURRENT_USER\Software\Microsoft\VisualStudio\<version number>\SourceControl.

4. Select the key DoNotCreateSolutionRootFolderInSourceControl, and click Edit, then Modify.

5. In the Value data box, change 0 to 1.

6. Click OK to accept your registry change.