Lost email since 10.11 upgrade

Hi, same problems: Nearly all passwords of my IMAP-Accounts had been lost on my iMac as well as on my MacBook Pro (but not: icloud- and gmail-accounts) and ports were different from the necessary settings. I talked to Apple Support and the told me that this happened to some people depending on their routers (in Germany: Unity Media, Vodafone...). Don't know the reason why this happened as a result of the El Capitan update. So I changed the ports of my email-accounts, put in the missing password - and everything is working! Try it out.

Depends on your account. Look it up in the settings of any other device (iPhone, iPad...) or ask Google!

My IMAP accounts are all fine but all of my other (mostly BT Yahoo) mail accounts that were setup as POP3 mailboxes in Mavericks have disappeared in El Capitan. Having tried to add these back (the accounts still exist in System Preferences -> Internet Accounts) mail shows them but all the mail that was in them is now gone and the actual email accounts cannot be accessed.

When looking at the type of account within Mail, Mail insists these are IMAP accounts and if you look in ~Library/Mail/V3 I can see that old email accounts there all named and full of content but I can't for the life of me, reconnect the mailboxes in the Mail app to the actual folders containing the data in the library folder.

Good job, Apple!! 😠

After I update to El Capitan my emails, emails account, account settings, filters ... everything disappeared!!!!

same here..grrr..

iCloud working..

my POP work account not.

Ports are ok, settings ok. nothing changed but all my emails are gone, including all my imported older emails.

Also suddenly have a copy of my POP account listed as an IMAP account in my email accounts that I'm sure was never there.

Nice job indeed. Will try a fresh install of my account tomorrow morning.

Not what I'm used to get from Apple. Can get it all back from my backups but it's annoying.

Update. Now my iPhone 6 is acting weird as well on Mail. Not sure if it's connected, but I suddenly have 4294967295 unread emails in my inbox...

Sigh.

Similar issue here. After making a clean install and using migration tool to retrieve settings from Time Machine, only my primary (iCloud) mail-account was displaying. Naturally i assumed that the other settings had been lost (2 gmail accounts), but when trying to add these in the mail-apps internal settings, it kept displaying "already logged in", which the Sytem settings seemed to confirm. Eventually I gave up tweaking the settings and removed the 2 gmail accounts from the System settings app, and added them in mail app settings. So far this appears to have resolved the issue, and all accounts arre displayed correctly in both setting-apps.

Great - this also resolved my POP3 issue.

1. Close Mail.

2. Go into System preferences -> Internet Accounts.

3. Delete the old POP3 mail account(s).

4. Re-add the old POP3 mail account(s).

5. Restart Mail, everything is fixed.

Great, although my posted workaround solved the problem for incoming mails, I realized that all my accounts were offline for smtp! And in Internet accounts my correct password wasn't accepted. So I deleted the accounts and re-added them. It's working for IMAP too! Thanks.

My iCloud account disappeared with the "upgrade," though my other accounts remained. Using the info from this page, I'm still unable to get it working. Each time I try to send mail I get a message saying the account can't be verified. I'm disgusted.

Update: I apparently fixed the issue by resetting authentication to password, but I'm still disgusted by Apple's careless disregard for user needs.

Hi Satchmo,

with this information from April 2015, you can't solve the problems of El Capitan from October 2015! Try to delete all internet-accounts and after this, re-add them. This works!

Try to delete MailData folder from username//Library/Mail/V3.

Mail Application will import again the mailboxes from all your accounts.

I hope this helps.

I have lost all emails which I had "filed" into mailboxes

Encouragingly Apple has contacted me about this issue with a case number of 664092518.