I had the same problem and I was able to fix it. Apple removed the POP email option in their software with the latest release of their operating systems - both OS X and iOS. Nevertheless, there is a backdoor way in Apple's software to set up a pop email account that works on OS X El Capitan Version 10.11.1 and on iOS 9.1. Remember, if you have even one device with an IMAP email account and delete emails with that device, you will delete those emails on your ISP's server and your other devices will not be able to get those emails. In other words, if you share an email account with multiple devices and all of the devices have IMAP email accounts, you will have a mess on your hands with one device deleting emails and your other devices not getting those emails.
We had this problem when my husband deleted emails on his new iPhone 6s thinking that they were only getting deleted locally on his iPhone and not on our ISP's server. He set up his email using IMAP as there was no other choice. Needless to say, I was very upset because I never got to read the emails on my device that he deleted on his device. I had a **** of a time figuring out how to change his email on his iPhone to a POP account. Nevertheless, I figured it out! The instructions are below.
Remember, it is important to set up ALL of your devices (iPhone, iPads, MACs, etc.) that access the same email account as POP accounts. Consequently, below are instructions for changing to POP accounts on both OS X and on iOS. Good luck!
Here is how to set up a POP email account on OS X El Capitan Version 10.11.1:
(1) Go to the MAIL program and click on MAIL in the horizontal top menu bar and select ADD ACCOUNT.
(2) Choose OTHER MAIL ACCOUNT for your provider.
(3) HERE IS THE TRICK: The next step asks you to enter NAME, EMAIL ADDRESS, and PASSWORD. For EMAIL ADDRESS, put an invalid email address such as kjfdkjdkj@kdjk.com. For PASSWORD, just type in anything, like klkdkjkle.
(4) Now, you will see a screen to correct the invalid email address. First, correct the EMAIL ADDRESS, USER NAME, and PASSWORD. Under ACCOUNT TYPE, notice that you now have an option to change your email account from IMAP to POP. The default is IMAP, so toggle to POP. Then, for INCOMING MAIL SERVER and OUTGOING MAIL SERVER, follow your ISP's instructions for what to type in those fields.
Here is how to set up a POP email account on iOS 9.1:
(1) Go to SETTINGS on your iOS device. Then, select MAIL, CONTACTS, CALENDARS.
(2) Select ADD ACCOUNT.
(3) Select OTHER for your email provider.
(4) Select ADD MAIL ACCOUNT.
(5) HERE IS THE TRICK: The next step asks you to enter NAME, EMAIL, PASSWORD, and DESCRIPTION. For EMAIL, put an invalid email address such as kjfdkjdkj@kdjk.com. For PASSWORD, just type in anything, like klkdkjkle.
(6) On the next screen, you get a choice to have an IMAP or POP account in the blocks on the top of the screen. Select the POP block.
(7) Now fill out the correct information with NAME, EMAIL, DESCRIPTION. Don't forget to fill out the information on the incoming and outgoing mail server information as instructed by your ISP.
I hope this helps!
