Mail constantly downloading messages

It just has the default IMAP folders. The Inbox has 17,000 messages and Sent has 7,000. Total of about 3.5 Gigs.

I have 5 email accounts. Two of them are very large with a large number of folders and several GB of emails. One account uses a MS Exchange server at my office. The other is an IMAP account through GoDaddy. Although I can't tell which account is being re-downloaded over an over, I believe that having a large number of folders and emails is part of the problem. It is interesting that both John Strung and I are using GoDaddy. Perhaps that is part of the problem. However, my iPhone is set up with the same accounts but it does not have re-downloading the issue like my Mac does.

One thing I did that helped was to clean up my email folders in both the IMAP and the Exchange accounts. I emptied the Trash, deleted everything in the Drafts folder and Junk folders, deleted old folders, and so on. My thought was to reduce the amount of folders/messages that need to be sync'ed. The re-downloading issue happens quite a bit less now (once every 2 or 3 days).

John: What about the other IMAP accounts for which you do not have this problem? Do they also have many messages? Mariano

> Although I can't tell which account is being re-downloaded over an over, I believe that having a large number of folders and emails is part of the problem.

You could check which one it is by disabling each of them in turn and seeing whether the one you leave enabled makes Mail's CPU to shoot up or causes the continuous message downloads. (It could be that both accounts cause problems.)

> However, my iPhone is set up with the same accounts but it does not have re-downloading the issue like my Mac does.

I also have my iPhone using the IMAP account that causes the problem in the Mac, but no problem there. (I had no problem with Yosemite, and 3 other mail clients in the Mac with El Capitan have no problems either. Problem showed only with Mail in El Capitan.) It could well be that the problem is only in El Capitan, and not in IOS.

Mariano

I also have no problem with the same account on my iPad or iPhone.

@Figante - the next largest account has about 10,000 messages and is about 2 Gigs in size.

El Capitan 10.11.3 was just released. Anyone tried it already? Anyone knows whether there is a solution to this problem?

I just did the update. I can confirm it did not fix the problem. Like many people above, I have not had any luck with any of the many fixes people have recommended. It is very frustrating as my computer is constantly redownloading every single day, I am downloading upwards of 30gb per day of emails I already have. It is very very frustrating as this is my primary computer for work emails. Often during the day I will flag some emails, and a few minutes later there is nothing newer than 2 years prior, after a few minutes and several thousand more emails downloaded, my current emails are back. This cycle goes all day long. It's so bad that I have resorted to using web based email from godaddy for much of the day. I have 2 work email addresses Imap to my work domain hosted on Godaddy, and 1 regular gmail address. I'm not sure but it appears they all have the same issue.

Anyone who uses their Mac for work must be losing their minds just as I am currently. I've been working like this for over a month with zero help from apple, and any fixes people have posted don't seem to work for me. I'm at my wits end with this issue.

Me too. And the strange thing is that I have about ten different e-mail accounts. The only one causing a problem is one GoDaddy account. I have 6 or 7 other GoDaddy and Gmail accounts that don't have this problem. The problem occurred only after upgrading to El Capitan.

I am probably going to jinx myself, but my Mac Mail has not re-downloaded any messages for the last several days, so my problem may be fixed. Unfortunately, I can't tell you exactly what may have fixed it, but I can tell you the steps I took (that I can remember):

1. I cleaned up my IMAP and Exchange accounts. Outside of Mac Mail, I went into my IMAP accounts via Webmail and my Exchange accounts at work and deleted my trashed messages, drafts, junk, ect. Deleted old or unused folders. Archived old messages to the extent possible. Really you should be doing these things anyway.

2. I did some crazy toggle of a Mail setting that I read about. I opened Mail, went to the the Mail menu - Preferences - Accounts. Selected one of my accounts. Unchecked the box for "Automatically detect and maintain account settings." Close Preferences. Quit Mail (not just the red x, actually go to the Mail menu - Quit Mail). Reopened mail. Went back and re-check the box I had just unchecked. Quit mail, then reopen it. I did this for all of my accounts. Tedious I know.

3. In Mail I went to Mailbox menu, then to Synchronize and selected each of my accounts.

When it did re-download thousands of emails for the final time, I sat there and watched it. I didn't close Mail, and I didn't let the monitor turn off or the computer fall asleep. I know it could be total coincidence, but I haven't had the problem since.

I can confirm that the problem is still there in 10.11.3...

Do Apple techs and engineers ever visit these pages to see that there are some major issues going on with their Mail program? I'm wondering if Godaddy will do something about it. If everyone out there like me has their computer downloading close to 40GB per day of email constantly, they may start to wonder why massive amounts of bandwidth are constantly re-downloading.

Quit Mail.

Go to Library (hold down alt in the 'Go' menu in Finder)

then find the 'Mail' folder > V3 > MailData and move the 3 files that start with 'Envelope' to your desktop.

Restart Mail. It will begin to Import your messages as before. This can take a while and even look like its stopped sometimes. Give it time it will eventually finish and then once its done you should see its stopped downloading/retrieving messages. If all is well delete the 3 files from your desktop.

Doing this essentially rebuilds the database by forcing Mail to reimport everything.

I've already done that process once to no avail. I've honestly tried most of the fixes going around currently. I'll give it another shot though just to see.

I saw the V2 folder mentioned but not V3. El Cap uses V3 mail folder. If you change anything in v2 it won't affect anything As it upgrades to v3 when you first start mail in el cap. Give it ago. If you've done it already then fair play. Doing what I said worked for me. Can't say it will work for everyone though unfortunately.

I think you may be right, I believe it was the V2 folder. The V3 looked different than the last instructions I followed. So far I did it and now its slowly plucking away at downloading my tens of thousands of emails. I'll keep you posted if I have success tomorrow. Thank you for the tip.