This topic

Unable to add second BT Internet Email to Classic Outlook using Microsoft 365 Windows 11

R_A_898 — Thu, 09 Apr 2026 14:56:38 GMT

When I try to add my second email address via selecting Advance Option > "Let me set up my account manually" in Classic Outlook, and choosing IMAP, I get the following error. My primary/initial email address works fine.

Re: Unable to add second BT Internet Email to Classic Outlook using Microsoft 365 Windows 11

gg30340 — Thu, 09 Apr 2026 15:18:54 GMT

Make sure you are adding the correct settings exactly as shown in the attached link.

BT Email server settings | BT Help

Re: Unable to add second BT Internet Email to Classic Outlook using Microsoft 365 Windows 11

R_A_898 — Thu, 09 Apr 2026 15:40:55 GMT

Hi,
Thnaks for the pointers.

The only change I needed tomake was setting the Outgoing SSL Encryption to "STARTTLS" from "SSL/TLS".

But I still get an error, when Outlook perfoms the "Test Account Settings"

Any other thoughts/idea would be great.

Thank you

Re: Unable to add second BT Internet Email to Classic Outlook using Microsoft 365 Windows 11

gg30340 — Thu, 09 Apr 2026 16:06:09 GMT

The setting as per the link I posted should be SSL Encryption: Enabled but not STARTTLS

Can you post a screen print of your settings. Make sure you obscure your email address prefix and password if it is showing.

Re: Unable to add second BT Internet Email to Classic Outlook using Microsoft 365 Windows 11

R_A_898 — Fri, 10 Apr 2026 08:20:44 GMT

Hi,

Sorry about the delay.
Screenshots of the Account Setup are:-

Then Password Entry - okay

Next ....

I have tried troubleshooting and that gets me nowhere when i follow the suggestions.

Thanks again,

Re: Unable to add second BT Internet Email to Classic Outlook using Microsoft 365 Windows 11

gg30340 — Fri, 10 Apr 2026 09:43:54 GMT

I don't use Outlook so I can not say if this will work and I know the BT page said not to use SPA authentication how ever on the email clients that I use there is a drop down down box for authentication and on one client it is able to select Plain or on another client Automatic.

I would suggest that you try ticking the Authentication box in the server to see if it offers a choice and if it does not try it anyway to see if it works.

The other thing is if you already have a working account have you checked what its settings are?

Re: Unable to add second BT Internet Email to Classic Outlook using Microsoft 365 Windows 11

R_A_898 — Fri, 10 Apr 2026 09:50:53 GMT

The working version is as suggested previously, but was set-up pre-Windows 11.

It is:-

And

I have previously tried setting the SPA flag but with no success

Thansk again

Re: Unable to add second BT Internet Email to Classic Outlook using Microsoft 365 Windows 11

gg30340 — Fri, 10 Apr 2026 10:22:18 GMT

Unless your previous screen shot has been cropped , you are getting a different authentication option on the first account you set up. It is letting you authenticate using your username and password in the out going server.

If it is not a screen crop did you use the "manual" set up method or the "automatic " method when you set that account up?

If the post is correct and the option is not there I would be inclined to start again and remove the new account from Outlook and restart your computer then this time let the account be set up using the "automatic" method as against the "manual" method that you used to see if that sets it up.

Re: Unable to add second BT Internet Email to Classic Outlook using Microsoft 365 Windows 11

R_A_898 — Fri, 10 Apr 2026 16:14:06 GMT

Yes, sorry, it was cropped, as I/it cannot show both Outgoing and Incoming at the same time.
Please see full pop-ups now:-

and

Thanks again.

Re: Unable to add second BT Internet Email to Classic Outlook using Microsoft 365 Windows 11

licquorice — Fri, 10 Apr 2026 15:50:06 GMT

To verify if the problem lies with BT or Outlook, try setting the account up in a different client such as Thunderbird or EmClient.

Re: Unable to add second BT Internet Email to Classic Outlook using Microsoft 365 Windows 11

R_A_898 — Wed, 22 Apr 2026 13:12:16 GMT

After setting up on Thunderbird, I have tried yet again and got it to work.
Outlook is the problem.
Thanks again for all the help and support.

I believe the ultimate problem lies with BTinternet emails and how they are set up compared to industry standards.

Re: Unable to add second BT Internet Email to Classic Outlook using Microsoft 365 Windows 11

licquorice — Wed, 22 Apr 2026 14:09:39 GMT

The settings for BT mail ARE industry standards.

Re: Unable to add second BT Internet Email to Classic Outlook using Microsoft 365 Windows 11

gg30340 — Wed, 22 Apr 2026 14:32:09 GMT

@R_A_898wrote:

I believe the ultimate problem lies with BTinternet emails and how they are set up compared to industry standards.

Can you explain how if the BTMail settings for email clients/apps are not " to industry standards" can the hundreds of thousands if not millions of people including yourself when you use Thunderbird, manage without any problems.

I would suggest that the problem is with 29 year old Classic Outlook and its compatibility with Windows 11.