Outlook might not actually be checking with the server for the limit at all. However, when you are using Outlook with a POP3 or IMAP account, Outlook could also nag about exceeding the allowable limit set by the server, even though you didn’t.īy setting a Registry value, you configure when Outlook starts reminding you about the total message size or disable the nag screen completely. The attachment size limit, or actually message size limit as it includes all your attachments and the message itself, is determined by the sending size limit configuration of the mail server that you are using. How can I increase the attachment size limit? When I try to send a message with some attachments, I get the warning that my message is too big to be sent.
