Postal Explorer > IMM Issue 35 - International Mail Manual > 4 Treatment of Outbound Mail 4 Treatment of Outbound Mail 4 Treatment of Outbound Mail 410 Postmarking 420 Shortpaid and Unpaid Mail 421 Check for Sufficient Postage 422 Unpaid Mail 422.1 With Return Address 422.2 No Return Address 423 Shortpaid Mail 423.1 General Procedures at the Mailing Office 423.2 Exceptions 423.3 Credit for Postage Paid 423.4 Parcels at Other Than Mailing Offices 430 Improperly Prepared Mail 431 Insufficient Address 432 Oversized or Undersized Items 433 Oversized Cards 434 Reply–Paid Cards 435 Detached Customs Declaration Forms 440 Extra Services Mail — Registered Mail 441 Recording and Dispatching 442 Registered Mail Found With Ordinary Mail 442.1 Disposition 442.2 Complete the Registration Process 442.3 Shortpaid Mail 450 Forwarding