Extract this 3 folders (use 7-zip for guaranteed success) to the desktop and then move them to your /Steam/Steam Apps/common/il-2 cliffs of dover/ folder.
Allow overwriting.
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Win 7/64 Ult.; Phenom II X6 1100T; ASUS Crosshair IV; 16 GB DDR3/1600 Corsair; ASUS EAH6950/2GB; Logitech G940 & the usual suspects

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