in GTA san Andreas definitive edition PC game, the Savegame location is at a different location or place, and in the old GTA San Andreas PC game, the save game location is at a different place.
Save Game location on windows PC
C:\Users\yourcomputeusername\Documents\Rockstar Games\GTA San Andreas Definitive Edition\SaveGames
That means first you have to in documents, then in the Rockstar Games folder, then you have to go inside GTA san Andreas definitive edition folder, and last you have to go inside the SaveGames folder.
by knowing the savegame location, you can safely copy your saved file to a safer location.
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