Originally Posted by Check Essential

I've had this on my sked. It means OK NO FLY.
They've never said a word to me but here's what somebody told me is going on:

Are you a captain that has not flown for 30 days or more?

I think OKNF is a code generated by the chief pilot. Skeds has a red flag pop-up and checks with the chief pilot or duty pilot to see if its OK to fly you or if you need a couple legs of "warm-up". You generally do not need anything if you've been on the airplane for awhile. If there's no other issues and you're just a reserve who hasn't flown -- you just get automatic OKNF.

If you are a new captain or new on the airplane or if there is something else going on with you I think they might give you a call and have a chat. They might offer you a warm-up with a check airman if you want one. Its not a check ride. If its been 60 days or something then maybe they require a warm-up. I'm not sure what the exact policy is.