Platforms
Source: Any Destination: Google Workspace or Exchange / Microsoft 365
Problem
When migrating mail into Google Workspace or Microsoft 365, the error message "Message is too large and attachments cannot be removed" may be returned for some items on import. It occurs when a mail item exceeds the default 50MB size limit in Google Workspace and Microsoft 365.
Solution
Exchange / Microsoft 365 destinations:
You can edit the Max Message Size in the Destination Platform Migration Settings accordingly (this is available as Message size is customizable in Exchange). It is, by default, set to 50MB, so provided the Exchange server allows message sizes of the same size that you set, it will then be possible to import them without error.
Google Workspace destinations:
The Gmail API now supports emails up to a max size of 50MB. If the message itself (not including attachments) is larger than 50MB, these messages cannot be imported to Gmail.