Post Office Protocol
- You use only one computer to check emails
- Emails are downloaded to the particular computer
- Allows you to keep your email messages only limited by the size of your MailClient.
- Emails are only downloaded and not synced. For other devices to have the same emails or webmail to still have the emails shown, “leave a copy of messages on serve” needs to be enabled.
- Emails can still be accessed after they are downloaded even if not connected to the Internet
- Outlook 2003/2007 .pst file is limited to 2GB or Outlook Express folders are limited to 2GB each
All emails are stored on the computer itself so if the computer is damaged/lost/stolen, the emails will not be recoverable.
Internet Messaging Access Protocol
- You use many different computers/devices to check your email
- Emails are stored on the server
- Your administrator can set users quota through the Email Control Panel
- Emails are not downloaded but synced (access direct from server). What you see from your computer, you will see the same on your other devices as well as webmail
- All emails are stored on the server so if the computer is damage / lost / stolen, just replace and recreate the account and all emails will be recovered
- Internet access is required at all times for emails to be accessible
- Limited by the server mailbox size quota for how many messages you can keep (this includes all folders, even the Trash folder)