Airmail didn't leave the Isle of Man yesterday.
The Isle of Man Post Office says the problem arose due to 'an issue' with its supplier's aircraft.
The upshot is that no airmail can be delivered to Royal Mail for subsequent delivery.
But it also means no airmail, special delivery items or Parcelforce24 mail was delivered to the Isle of Man today.
Local-to-local and sea mail remains unaffected.
An Isle of Man Post Office spokesman said: 'Our supplier is attempting to resolve the issue with the aircraft today so airmail can leave the island this evening but we will update if any further disruption is anticipated.'
The Isle of Man Post Office has had similar problems frequently in the last few week.