Email Server Problems

Question

I've been using Outlook Express as my preferred Email Portal for 25+ years without any connectivity problems, even when I was using dial-in. I've been with BT as my ISP since returning to the UK in 2001 and over the last 18 moths have been experiencing numerous unfathomable error messages when connecting. "Password not recognised," "Server timed-out due to inactivity," (when first logging in) and being forced to use my sub-accounts to send and receive messages.
This is an annoingly intermittent problem with not set pattern of failures. Numerous calls to the Help Line have been useless, as they have looked around and seen no problems with my Server settings (POP3) A recent call to the Tech Help line (that I reluctantly paid for) saw the lady I spoke to, take control and change my POP3 In-Out settings and all has been fixed (it seems)
I have a new Windows 8.1 PC (still in the annoying set-up process) onto which I have installed MS Office Professional Plus 2010, and the Outlook settings showed as my old POP3 configuration. I changed it to the new ones the Tech Desk set up but I still cannot get on it to send/receive as I get an Error/Warning that says the IMAP Server has disconnected. The Outlook Account Settings do not have IMAP in the Pull-Down menu to choose as an option for connecting.
I used to be up-to-date with IT matters, but now I'm dreadfully confused.

Answer 1

Outlook can be set up as either a POP account or an IMAP account. You can not change a POP account to IMAP account on the fly. Yoy will need to either delete the POP account and start again or setup an IMAP account to run in tandem with the POP one. Once up and running you could then delete the POP account.
You are best to set it up manually by ticking the "manually configure server settings"  and enter all the settings rather than using the set up "wizard"
The settings you need to use are:
Your Name
Email address: Full btinternet email address
Account type: IMAP or  (POP)
Incoming server: mail.btinternet.com  
Outgoing server: mail.btinternet.com
Logon information:
User name: prefix only of email address
Password: Email password
Tick remember password
Do not tick Require password auth (SPA)
Click Button More settings
Tick box my out going server requires authentication
Tick box use same as incoming
Do not tick log onto incoming server
Advanced Button
Incoming server 993 or (POP 995) Tick requires SSL
Outgoing server 465 Use following type encryption SSL