Choosing between IMAP and POP
Most email clients give you a choice between using IMAP or POP (also called POP3). Either choice works, but both have pros and cons.
- IMAP - the email lives on the server and the client is merely listing it
- POP - the client takes the email into its own storage, typically deleting it from the server.
POP Pros and Cons
- Mail stored locally, i.e. always accessible, even without internet connection
- Internet connection needed only for sending and receiving mail
- Saves server storage space
- Option to leave copy of mail on server.
- Consolidate multiple email accounts and servers into one inbox
- Can use rules to sort mail into folders
- Lose your device / PC, lose your emails. If you did not back them up they are gone forever, there is no server copy or backup.
IMAP Pros and Cons
- Mail stored on remote server, i.e. accessible from multiple different locations
- Internet connection needed to access mail
- Faster overview as only headers are downloaded until content is explicitly requested
- Mail is still there even if you lose your device / PC.
- Server fills up: The email lives on the server and often accumulates as folks tend to skip spam / unwanted / no longer wanted emails and not delete them. The server fills and eventually stops receiving email for that account.
- Cannot use mail rules to sort emails into folders
- Harder to make folders
- Can be hard to delete – some email clients have an obscure extra "purge" step.
- Cannot combine multiple IMAPs into one inbox.
Using Multiple Email Clients
The easiest way to have multiple email clients is to have all use IMAP, so all see the same thing all the time.
POP works and does not fill up the server if a special option is always set. Most email clients have in their advanced settings something that controls if the emails are deleted after being POPed down. Also there is typically an option to "delete after 10 days" or something similar. You can chose one POP client to be the only one that deletes, and set it to delete only after some days. As long as the other clients POP in before these days expire they get all the emails.
POP Ate My Emails
A cautionary tail: multiple pops can cause your emails to be lost.
If you have more than one POP client, and if they delete the email after downloading, then each client gets only some of the emails. Example:
- Emails A and B arrive
- Client 1 POPs in and gets the emails and deletes them
- Emails C and D arrive
- Client 2 POP in. Emails A and B are not present, emails C and D are downloaded and deleted
- Client 1 POPs in, does not find emails C and D
User is hoping mad, asserting that emails get lost.