How can you appeal Microsoft throttling?

Appealing Microsoft throttling requires patience and proper process. First, ensure you are actually throttled rather than blocked; 421 errors indicate throttling while 550 errors indicate blocking. For throttling, the primary response is reducing sending speed and implementing proper retry logic.

For persistent throttling or blocking issues, Microsoft offers a sender support form through their postmaster portal. Submit your sending IP, describe your email program, and explain what steps you have taken to address potential issues. Response times vary from days to weeks.

Microsoft rarely provides specific feedback about why filtering occurred. Appeals work best when you can demonstrate legitimate sending practices, proper authentication, and active list management. Include information about your opt in process, complaint handling procedures, and any recent changes to your program that might have triggered issues.