Client-specific message size limits - or the reason why iOS won't sent emails
Last week, a customer complained that he could not send emails with pictures with the native iOS email app. He attached three, four or five pictures to an emails, pushed the send button and instantly an error was displayed.
We checked the different connectors as well as the organizational limit for messages. The test mails were between 10 to 20 MB, and the message size limit was much higher.
The cross-check with Outlook Web Access indicated, that the issue was not a configured limit on one of the Exchange connectors. Instead, a quick search directed us towards the client-specific message size limits. Especially this statement caught our attention: