This is a scam. The genuine OFID (OPEC Fund for International Development) website states:
As an infallible rule, OFID does not extend loans or any other form of financing to individuals.
From: OFID <[email protected]>
Date: Wed, Sep 22, 2010 at 5:35 AM
Subject: OFID Grant/Donation Award
N:B; Grant Qualification Code ( OFID/OGA7/OA8/45 )
You have been awarded the sum of £745,816 British Pounds Sterling as Grant Donation/Award from OFID. To redeem your award, contact Mr. Fred Thickins by replying to this notification.