Thunderbird stopped connecting to BT Email servers

[MartynAJ]

I use Thunderbird as an email client on my laptop. On the 8th August 2026, Thunderbird stopped receiving emails. No error message detected.

BT Mail client works on my phone, and Webmail works.

I changed my password, and got no error response when I attempted to get email in Thunderbird. Password was not reported as incorrect.

I was connected using a  VPN for security reasons. 

I tried the connection without the VPN active, and the incorrect password was detected. Changing the password on my client resulted in emails being received correctly.

No notification regarding VPN usage had been received.

Is this a policy change by BT?

[licquorice]

No, if you search through the forum there are many reports of VPNs causing problems with email.

BT email is encrypted anyway so no need for a VPN.

[MartynAJ]

I generally use the VPN for security.
Until the 8th August, I was always able to receive emails in Thunderbird so why has it changed?
And how does the encryption work in a third party email client?

[licquorice]

As long as you are using the recommended ports 993 and 465, your mails are SSL encrypted end to end.