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How to know the MailStream Plus monthly Postal Reference Files are provided in a .zip file

MailStream Plus - all versions, all platforms
 
The monthly Postal Reference Files are provided in a .zip file, and can be downloaded from www.g1.com/support, or from the Pitney Bowes eStore.
Once the file is unzipped, there will be 12 .MSP files that are the raw files to be loaded into MailStream Plus per the instructions and program for the specific platform (z/OS, IBMi, Windows, etc).  The loading instructions are found in the MailStream Plus Installation Guide.

(Note that on the Windows Platform, .MSP files are seen as Windows patches.  But you do not execute them directly, you load them per the instructions in the MailStream Plus Installation Guide.)
 
UPDATED:  July 27, 2017