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Thunderbird email "unable to connect" on second account, no problems on first account

  • 6 replies
  • 4 have this problem
  • 1 view
  • Last reply by sfhowes

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Setting up a desktop (Dell Inspiron) for neighbors using latest Linux Mint (21.3 Cinnamon). They have simple needs, LibreOffice, Firefox and email. Plain jane, nothing extra added, straight from latest Mint install.

I am having trouble adding a second email account in Thunderbird (115.8.1). First comcast account was very easy, standard comcast defaults, works fine, downloads and sends. Second comcast account keeps giving "Unable to Connect" poput screen. (https://localhost/?code=0.ac.w2.PciwTw)

I can login to either Xfinity email account through Firefox browser using same addresses ((username)@comcast.net) and passwords I am using to attempt to add second account in Thunderbird.

Tried it with Mint Firewall off, then on, then off again. Do I need to setup firewall for second account?

Can someone give me a hint on this problem? Is is Thunderbird? Comcast? Something else?

Setting up a desktop (Dell Inspiron) for neighbors using latest Linux Mint (21.3 Cinnamon). They have simple needs, LibreOffice, Firefox and email. Plain jane, nothing extra added, straight from latest Mint install. I am having trouble adding a second email account in Thunderbird (115.8.1). First comcast account was very easy, standard comcast defaults, works fine, downloads and sends. Second comcast account keeps giving "Unable to Connect" poput screen. (https://localhost/?code=0.ac.w2.PciwTw) I can login to either Xfinity email account through Firefox browser using same addresses ((username)@comcast.net) and passwords I am using to attempt to add second account in Thunderbird. Tried it with Mint Firewall off, then on, then off again. Do I need to setup firewall for second account? Can someone give me a hint on this problem? Is is Thunderbird? Comcast? Something else?

Chosen solution

OK Fixed it and was able to add the second email account (from a single xfinity account) using the following settings: The settings for email in Thunderbird should be: Incoming Mail Server Name: imap.comcast.net Port Number: 993 Connection Security: SSL/TLS Authentication Method: Normal Password User name : full comcast email address.

Outgoing Mail Server Name: smtp.comcast.net Port Number: 587 Connection Security: STARTTLS Authentication Method: Normal Password User name : full comcast email address.

HOWEVER The first email account is still using the default Authentication OAUTH2 instead of "Normal Password" for both in and out, and SSL/TLS for the connection in outgoing. Who knows? At least it is working...

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All Replies (6)

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Have you enabled 3rd-party access for all accounts?

https://www.xfinity.com/support/articles/third-party-email-access

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Have you enabled 3rd-party access for all accounts? Thanks for reply. Comcast likes to use last login. Finally got to the Ladies account on Firefox, bit was not set to allow 3rd, so I changed it. Her email page shows Mans name?? on Firefox Xfinity. Struggled but managed to login on Mans account, (first and working in Thunderbird) it WAS set to allow.

Still get "Unable to Connect" popout screen when attempting to add second, Lady's account.

Do we need to contact Comcast for such a problem?

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If both accounts have allowed 3rd-party access, and the settings are the same except for User Name, I can't see why the second one can't be added. The fact that both accounts can be accessed with a browser using the first account's credentials, makes me suspect the second account is a sub-account of the first, not a separate, independent account.

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Agree totally! Hence my frustration.

However, the two email lists when logged on in Firefox are different.

I am sure they are both on the same single Comcast account.

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Chosen Solution

OK Fixed it and was able to add the second email account (from a single xfinity account) using the following settings: The settings for email in Thunderbird should be: Incoming Mail Server Name: imap.comcast.net Port Number: 993 Connection Security: SSL/TLS Authentication Method: Normal Password User name : full comcast email address.

Outgoing Mail Server Name: smtp.comcast.net Port Number: 587 Connection Security: STARTTLS Authentication Method: Normal Password User name : full comcast email address.

HOWEVER The first email account is still using the default Authentication OAUTH2 instead of "Normal Password" for both in and out, and SSL/TLS for the connection in outgoing. Who knows? At least it is working...

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TB 115.6.1 added OAuth2 support for Comcast, although Comcast has supported it for a few years. Since not all mail apps support OAuth2, Comcast still allows 'normal password'. The outgoing smtp.comcast.net works with SSL/TLS on 465 and also STARTTLS on 587.