To make changes to a file you must first check it out of the VSS database. When you Check Out an item, VSS places a writable copy in your working folder. A file that is checked out cannot be checked out by anyone else unless your installation of VSS has been set up to allow multiple checkouts; see your VSS administrator for more details. You can see who an item is checked out to in the User column of the file pane. You can check out one file, multiple files, or all files in a project depending on what item(s) you have selected when you perform the checkout operation.
In addition to checking out an item, you can also View or Get the item. See Get and View Files and Projects for more information.
When a file is checked out, the following options are available:
For information on how to check in, check out, and edit files and projects, refer to: