Mail.dat® File Validation: How to Make Sure Your Files are Valid

Mail.dat files are valuable tools for mailers, mail service providers, logistics companies, and the United States Postal Service® (USPS®).  Mail.dat files contain virtually all the information regarding a specific mailing with the exception of names and addresses.  Mail.dat files may be used to communicate information about mailings, edit and manipulate mailing information, analyze mailings for drop shipping or other work-sharing discounts and combined mailing opportunities, and to facilitate the generation and transmission of postal documentation.  As valuable as this tool is, however, it is not much use if the Mail.dat file is not “valid”.

Whether you are generating your own Mail.dat files or you receive them from outside sources, it is crucial that you validate the files before you begin using them.  Most Post-Presort™ software utilities have the ability to perform Mail.dat file validation, and depending on the software, you may or may not be able to import Mail.dat files containing errors.  Good post-presort software will import the files and provide detailed reports of any errors detected.  Post-presort software should also allow you to easily locate these errors in the Mail.dat files to make corrections without having to regenerate them.  There are a number of checks that occur when the validation process is performed.  Ideally, the error report generated by the software will classify the errors as to their level of severity.  Critical errors would be those which must be corrected before the file is used.  Lower level errors should still be corrected, but may not interfere with accurate processing of Mail.dat files, or can be easily corrected without re-generating the files.  There are also different industry standards that you can validate against: IDEAlliance® Mail.dat specifications, PostalOne!® specifications, or proprietary software specifications.

Important Mail.dat validation items:

§  The Mail.dat specification version number.  Robust validation software will not only detect the version number, but will update the Mail.dat file to the most current version specifications

§  Missing or incorrect information in required fields

§  Incorrect formatting of data (i.e., alpha characters in a numeric-defined field) 

§  All required files are present.

Obviously there are numerous items that need to be checked during the validation process, and the size of the Mail.dat files prevents this validation from being done as a manual process.  Only by utilizing a very robust, flexible, post-presort software solution can you be assured that your Mail.dat files have been prepared properly and are valid.