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ValveTime.co.uk | Valve News, Forums, Steam
i think ive found a fix for the memory read error on HL2, it might only work if you preloaded the files from steam tho.
go into the 'HL2' folder in your 'SteamApps' (program files, valve, steam, steamApps, *your steam username*, Half-Life 2, HL2)
go into 'Save' and move all of your save files onto your desktop if you want to keep them
delete everything INSIDE the 'HL2' folder. do not delete the folder itself
after youve deleted it launch the game
exit the game and go back to your 'HL2' folder, all of the files should be there again, just put your save games back into the save folder and that should fix the error