How long does it take for an AdMob Ad unit ID to become active?

Question

I created a new Ad unit ID around 4 hours ago and started using it in the release build of my unreleased Android app. But all I get is a blank view and the following logcat output:

W/Ads: Received error HTTP response code: 400
W/Ads: There was a problem getting an ad response. ErrorCode: 0
W/Ads: Failed to load ad: 0

Since the the Ad unit IDs for the other apps in the same AdMob account work - even when used in the app in question - the best explanation I can come up with is that the new ID hasn't been activated or properly propagated yet.

How long does this usually take or what am I missing?

Answer 1

I don't know the exact time it took but 12 hours after creating the new Ad unit ID it was active.