Getting local POP mailbox messages into Gmail

Question

I currently bring my Gmail mail into Thunderbird via POP for backup purposes (POP is just the way I roll).

Should I ever need to push that mail back onto Gmail via IMAP using Thunderbird - is the fact that the messages were originally retrieved via POP going to prevent them being pushed back onto Gmail?

Answer 1

No, that should not be a problem. Just drag them from your local mail folder and drop them into the imap folder you want copy them to, or use right-click and move-to.

You'd first have to configure imap access to the target account (not necessarily the same account the email was originally sent to) then you can move your local email to the INBOX that is listed under that account - or (maybe preferably) you could create a new imap folder under the imap account (let's call it "Archive") and move your email to that new "Archive" folder on the imap server.

I don't know how Thunderbird would handle having both an imap account and a pop account both pointing to the same actual email account. I'm not saying that's what you're thinking of doing, but it sounds undesireable to me. (That might be another superuser question if that's what you want to do.)

The dates (and all data, including attachments) should be preserved, but I'd suggest starting with one or two emails just to be sure it does what you expect. This is definitely the type of thing you'll want to experiment with for yourself before you try to move large amounts of email.

Answer 2

The method you used to fetch the messages into Thunderbird makes no difference. The only thing that matters is where the messages are. For POP, the standard is to store messages on the local system in the local client's data store; this is not necessarily the case depending on your Thunderbird mail settings.

I'm not sure how you would get the messages into Gmail - remember that IMAP is a server protocol, so it is your server that must talk IMAP. I suppose you could copy the messages in somehow.

Remember through all of this: POP and IMAP are not secure. If you use SSL, then you are alright - but the technical term for those protocols are POPS and IMAPS.