Without knowing knowing anything about where you are in the game is going to be difficult.
In the 1st witcher game the named saves are by location. i.e. Salamandra hideout, Country Inn, Abigail`s house, etc. So unless you know exactly where you were when you stopped well you get the idea.
In renaming a save it would need to look something like this
000001 - Outskirts-001
But if you`re in the prolog I would just start over since it`s not that long