Why the Updates:
The USPS® periodically makes updates in the PostalOne!® system to incorporate enhancements and bug fixes to their software. Major changes are performed when there are significant changes to postal rates or regulations, such as when the USPS increases their prices in January each year. There are usually a minimum of four PostalOne! software updates during the year: January, April, July, and October. There may also be interim updates to PostalOne! for immediate fixes or other system issues.

Handling Changes:
When these types of changes are announced, it is important for mailers to pay attention to the outage periods so that you can make adjustments in your mailing operations to accommodate the downtime. Also, it is important for mailers to download and install the USPS Mail.dat® Client software (also sometimes referred to as MD Client or MDR Client) as soon as it is available. This software can be downloaded from the Business Customer Gateway web site. Mailers also need to make any associated updates or configuration changes to software that interfaces with PostalOne! once their Mail.dat Client software is updated.

USPS Resources:
So that you don't forget about these critical updates, the USPS sends out notifications of all PostalOne! outages and software updates using the DMM Advisory. You can subscribe to the DMM Advisory by sending an email to PostalOne! also sends out update notifications to PostalOne! users who have asked to be added to the notification distribution list. To make this request, send an email to In addition, detailed information regarding the changes in the PostalOne! software are available on the USPS RIBBS web site. Also available on the RIBBS® site are the planned release schedules for these updates.
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