I think this post might help. Sound like the resx file is missing and you want to know how to regenerate it?
Open the Form1, right click Properties, look for the Localizable property, turn it to true then to False. You should see a new Form1.resx file being generated.
But what are the contents in it previously, that a different story. That why we all should check in the code into a repository.
.net - Is there a way to regenerate a missing .resx file? - Stack Overflow[
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