Policy
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.
Pack Microsoft Office
Category Microsoft Outlook 2016 / MIME to MAPI Conversion
Policy ID
d2183ac65872 Internal name
L_Changelimitrecipients Registry
Copy registry mappings
HKCU\software\policies\microsoft\office\16.0\outlook\options\mail\maxnumrecipientsPolicy notes
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.