How to: Undo a Checkout Using a SourceSafe Plug-in
The SourceSafe plug-ins for Visual Studio support an Undo Checkout command. This command is almost identical to the Visual SourceSafe Undo Check Out command, which allows you to revert an existing checkout. Depending on the options you set in the advanced options of the Undo Checkout dialog box, the SourceSafe plug-in either replaces the file with a version from source control (the default option), leaves your local copy of the item unchanged, or deletes it.
To undo a checkout from a SourceSafe plug-in:
In Visual Studio, open Solution Explorer and select a checked-out item.
On the File menu, click Source Control, and then click Undo Checkout.
In the Undo Checkout dialog box, select the appropriate options, and then click OK.