iphone 5c "cannot get mail logins are disabled." How do you fix this?

This is an old thread, but the problem still occurs if you use an unsupported method of authentication on your iPhone, so for others I will explain how this works using Apple's Server App, but the most important information is that the error indicates that the authentication method on your iPhone must match one of the supported authentication methods on the server..

The mail server pane contains a section for authentication, where you can choose or select multiple options from:

• Kerberos
• Digest (CRAM-MD5)
• Cleartext
• APOP (POP Only)
• Digest-MD5

I have an Apple-only setup at home and I have Open Directory enabled, so I like to use the Open Directory preset (from the dropdown). If you have non-Apple clients this preset is safest to use as well.

You can change the authentication method of your iPhone email account through advanced settings of your account inside the settings app of your iPhone.

Since the Open Directory dropdown option enables all options that are 'safe' and that means the CRAM-MD5 option is enabled as well, I use this method of authentication on my iPhone.

If the server's supported and iPhone's utilized authentication method settings match, it could still be a problem of misconfigured passwords, but you can see this in the mail server error log inside Server.app --> Logs and select the Mail Server Error Log from the drop down menu. Just look for the user name you are using.

First thing I would do is check with my email provider to make sure:

1. Their service is not experiencing any problems.

2. That the entries you made in the Mail account are all correct.

Settings > Mail, Contacts, Calendars > Add New Account

Yes, that's the problem indeed. You'll either have to keep using webmail, or if they have an app, use it.