Exchange – Maximum Message Size for High Priority Emails

You may want to change the maximum message size for high priority emails, as the default value is 250KB. The “MaxHighPriorityMessageSize” parameter controls the maximum allowed size for a high priority message.

Navigate to the Bin directory and find EdgeTransport.Exe.Config file. Open it using notepad and find the line that says MaxHighPriorityMessageSize:

Change the value of “MaxHighPriorityMessageSize” from 250KB to the one of your choice, let say 5MB. You should get something like this:

If a high priority message is larger than the value of the “MaxHighPriorityMessageSize” parameter, the message is automatically downgraded from high priority to normal.

Written by Misha Hanin

Trusted Business & Technology Advisor, Solutions Managing Director & Senior Solutions Architect at iRangers International Inc. with more than 25 years of experience in the field of information technology, infrastructure analysis and design, implementing innovative and leading technologies for International companies around the globe in public and private sectors.

Over the years I was able to develop very strong technical and engineering skills which helped me to earn trusted advisor status with our clients. As one of the nearly 500 trained Microsoft Certified Masters (MCM) in The World (during 10 years existence of MCM program, just about 500 people in The World participated in this very intensive training), I have a winning track record in building and bringing projects to operational and measurable success.

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