I have read in past blogs a bunch of different maximum size attachments that Gmail will allow you to send through their SMTP servers so I wanted to verify directly through Google what the maximum actual attachment size was.
Maximum Gmail Attachment Size:
When settings up an IMAP account in Microsoft Outlook you will download only the headers by default. Personally I like to have all of my emails easily accessible online and offline even with IMAP accounts so below I describe how to setup your IMAP accounts to download the entire email message including any attachments.
Follow the below steps to setup a custom Outlook send and receive group. In this group you can pick and choose which accounts to includes and which IMAP folders to download. For each IMAP account you can specify numerous different options including if you want to sync a specific folder, if you want to download only the headers, or if you want to download the entire message including any attachments.