In Visual SourceSafe, rolling back a file returns the file to a previous version, erasing all the versions and changes since that version.
About the Rollback Command
The Rollback command is available by choosing Show History from the Tools menu of Visual SourceSafe. By default, Rollback affects the current project only. All changes made after the version rolled back to are lost. For example, if you choose version 5 for file and then use the Rollback command, all changes since version 5 are lost. For more information, see.
Rolling Back to a Version for a Shared File
When you use the Rollback command for a shared file or project, it branches the file in the specified project away from the same file in all other projects. This creates a new development path. If you make changes to the specified project and want to bring the separate development paths back together, you have to merge the files. For more information, see.
Undoing a Rollback Operation
It is possible to reverse a rollback operation. You can check out a rolled-back file, get an earlier version of it, and then check in the earlier version.