There is a Modern Warfare 3 campaign early access “disc required” error that has surfaced for some players. and here’s a potential fix.
Source: N4G PC Modern Warfare 3 Campaign Early Access Disc Required Error Surfaces, Here's a Workaround
There is a Modern Warfare 3 campaign early access “disc required” error that has surfaced for some players. and here’s a potential fix.
Source: N4G PC Modern Warfare 3 Campaign Early Access Disc Required Error Surfaces, Here's a Workaround