Here is my situation:

I'm the Systems Admin at my company, and I'm trying to connect to Outlook 2013 on a Windows 8.1 Surface Pro 3 to our company POP3/IMAP server. The devices are on a domain. As an admin, i have all permissions, and my SP3 connects fine. I have no issues. However, I have 2 other devices that do not connect at all. I get the error Authentication rejected. That said, the devices can send, but can't receive. They aren't able to log into our receiving server.

When this happens, as I'm trying to set up the mailbox for the user, the password is consistently cleared. The password does not store. I have tried using all setting for IMAP, using SSL, our proper settings, etc. I've tried the following for both POP3 and IMAP:

1. Clear and recreate the account
2. Clean boot
3. Tried a fresh install, no updates for either Windows or Outlook 2013
4. Start outlook in safe mode
5. use SSL ports that we have open, 993 and 465
6. used our domain mail address
7. tested my account on the same devices failing, with no issues
8. Gave the users the same permissions i have on the domain
9. used email address as username
10. Tried any number of other options grasping at straws to make this work

None of these things worked. 

Here are the errors I get:

Task 'username@maildomain.com - Receiving' reported error (0x800CCC92):'Your email server rejected your login. Verify your user name and password for this account in Account Settings. The server responded: -ERR Authentication failed.'

or, without using the mail address as the username

Log onto incoming mail server (POP3): Your e-mail server rejected your login. Verify your user name and password for this account in Account Settings. The server responded: -ERR Authentication failed.

Now, before you ask, yes, I've tried changing the password for my user. This didn't work. I'm not looking for the obvious answers. I've tried them all. I need more in-depth troubleshooting.

I've monitored the mail server when trying to connect, and the password, despite being input properly, hits the server blank, and clears the password in the setup of Outlook. The password is NOT saving on hand-off to the server for authentication. If I use a different mail program on these devices, they connect without issues. Thunderbird, Opera, etc. The only one not connecting is Outlook.

Initially, when I started setting these up, I had not issues connecting. The first device worked, till I did updates. I have checked the updates that I have seen could be the root cause, but the devices to have those updates.

On a side note, if I try to connect Outlook on a Windows 7 machine, with the users information, connects no problem. Or, if I use a different mail program, such as Thunderbird, on the SP3s, they connect no issue. If I take the devices out of the domain, they connect. In the domain, no connection to mailboxes, and creating the mailbox in a non-domain account, then created some weird shortcut to that mail, is not an option. This needs to work correctly.

PLEASE HELP!!