Transfer mail from local machine to Gmail

Question

I'm trying to use Gmail to manage a MS Exchange email that I log into with Outlook Web Access. The Exchange email has IMAP and SMTP access but not POP3 access so I can't use Gmail's "check mail from other accounts" feature but I can use the "send mail as" feature. An inbox rule to forward all mail to the Gmail account doesn't work either.

I want to use Fetchmail and something else, possibly Postfix, to retrieve mail from the Exchange email and pass it along to Gmail. I'm not sure what the proper name is for that second operation, that is, placing the retrieved emails in my Gmail but not sending them to Gmail. Maybe "transferring"? or "pushing" an email? This might be why I can't find what I want on Google. I don't I want to forward the mail. It should appear in Gmail as if I had used the "check mail from other accounts" feature.

Right now, Fetchmail works - I can retrieve mail from the Exchange server, but I don't know where to go from here or what terms I should be using to search. I think what I should be trying to do is use Postfix to transfer the mail to Gmail via SMTP but I'm unsure.

There are a few questions and blog posts out there by people trying to access Exchange with Gmail. Those all involve either forwarding (doesn't work for me) or using just Fetchmail. The Fetchmail-only solutions specify smtp.google.com as the smtphost in the poll. I can't get this to work and it doesn't make sense that it would since the Gmail password is never given. (Further searching - it looks like fetchmail doesn't support ssl on the smtp side.) Some solutions also suggest using Thunderbird to do this. I'd rather not.

I can't find anything on Google about people using Postfix to transfer mail to Gmail. Instead I find I lot of people relaying mail through Gmail.

Is the approach I've outlined sensible or do I fundamentally misunderstand something? Can I use Postfix to transfer mail, already retrieved, via SMTP to Gmail as described? What is the appropriate name for transferring mail like this?

EDIT: The transfer to Gmail should be automatic and regular. This is not intended as a onetime backup but rather as a way to receive email.

Thanks.

Answer 1

It appears as the only way to receive email from the Exchange server is via IMAP (or OWA). As a result, we're limited to tools that can talk IMAP (or possibly MAPI on the Exchange-side). Also I think the proper way to upload these messages to Gmail is to use IMAP (or possibly Gmail's API).

Since IMAP is the common denominator, and the most commonly used method for copying email messages, it appears to be the best tool in this case. You could perhaps try to deliver the messages via SMTP, but you would then be subject to Google's spam-filter etc, as well as the fact that the messages would be altered.

Now, if you had access to configuring the domain and/or server, you could have set up some kind of split-delivery (aka dual-delivery), but I'm going to assume that isn't the case here given the information you provided.

Let's go back to the possible solutions. The solution that stands out as the most obvious one to me is to use imapsync to fetch messages from the Exchange server and push them to Gmail. You could then run this every 30 minutes or so using crontab.

This does however come with some limitations, such as this being a one-way solution (ie. you never delete any messages from the Exchange server, so it might fill up).

You should be able to find plenty of examples of how to set this up using a quick Google-search.

Please note that you can also adjust imapsync to either sync just your INBOX, or other folders as well. If you're only getting inbound messages, and you have no rules that move messages, just syncing the INBOX should be sufficient.