As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT RETURNED TO PLATFORM AS A CONSEQUENCE OF IT WAS NOT POSSIBLE TO CLOSE THE CABIN CREW LEFT WINDOW. THE WINDOW WAS CHECKED AND THE FAILURE WAS CONFIRMED. THE ROD ASSY WINDOW MECHANISM WAS ADJUSTED IAW M/M 56-12-11, BEING CORRECT. DURING OVERNIGHT CHECK THE WINDOW WAS ADJUSTED AND ITS OPERATION WAS VERIFIED IAW M/M 56-12-11, BEING CORRECT.