Well as far as I can see it tries to access either a file or a part of it, but for some reason it cannot access that. Can you try running the gta launcher as administrator without steam (goto the install folder e.g. "C:program filessteamsteamappscommonGrand theft auto episodes of liberty cityeflc" then rightclick launcheflc.exe and select run as administrator)
That should sort it out if it cannot access the data due to invalid permissions.
Keep the peace,
weskey007