Increase the file size limit on attachments

Increase the file size limit on attachments

November 6, 2019

You can increase the maximum size of an attachment or attachments that can be sent in an Outlook email message by changing a setting in Registry Editor.  By default, Outlook will not allow you to send an email greater than 20 MB.   


In the menu under HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Preferences 



With this folder selected, go to Edit . . . New . . . DWORD (32-bit) Value and name the new file as 'MaximumAttachmentSize'. 


Double-click this new field, so you can edit it.  With decimal selected, enter a limit in KB - so 100,000 for 100 MB. 




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