Ah I see, maybe time for a new drive or whole new computer then. Thanks for your help

so I've lost all them hours of work? So how can I prevent this from happening again?

What would be the explanation for having to re-sign in then, as this has never happened before.

Hi, I play Factorio everyday and last played it yesterday and everything was fine. Load the game up today and im no longer logged in and have to log in and also when trying to load my save I get an error with this:

Opening zip C:/Users/Administrator/AppData/Roaming/Factorio/saves/lets try 2.zip ...