Q. In Microsoft Outlook, how can I identify emails larger than 18 MB ?
In Microsoft Outlook:
Expand Search Folders. This is typically found near the bottom of your list of folders.
Select Large Mail.
A search will be done on your entire Microsoft Exchange account and all emails that are flagged as large will be displayed. They will be sorted into categories such as "Enormous ( > 5 MB ), Large (100 - 500 KB), etc.
Each emailin the "Enormous" category will then need to be selected and reviewed to see if it exceeds the 25 MB limit set by Google. Emails that are larger than 18 MB should have the attachments saved to an alternate location and the email removed/deleted/archived.