Change the limit for the number of recipients

By default, the limit is 12288 recipients included for an e-mail message when the message is converted from MIME to MAPI. The number can be set to any positive integer. This helps prevent scenarios in which Outlook hangs while attempting conversion.

Supported on: At least Windows 7

Registry Pathsoftware\policies\microsoft\office\16.0\outlook\options\mail
Value Namemaxnumrecipients
Default Value12288
Min Value
Max Value99999


Administrative Templates (Computers)

Administrative Templates (Users)