Unable to sign-in when adding new email account into new Outlook in Windows 11 pro.

Question

Unable to sign-in when adding new email account into new Outlook in Windows 11 pro.

Rejean Paquet 0

image deleted for PII

are we allowed only 1 attached file?

I included the screenshot when I'm adding a new email account and it failed with Sign-in failed. But I am able to add the same email account with same server information to my Outlook on my iPhone. Also I have 3 other Comcast email accounts that are working on Outlook windows, so there is something about this particular email that Outlook doesn't like.

Rejean Paquet 0 Reputation points

2026-10-14T22:28:50.5233333+00:00

I renamed OLK and OneAuth folders, the I restarted Outlook, I had to re-add 4 accounts, they all working fine. One failed, the same I am having problem before = ******@comcast.net. Like I said, I was able to add it to Outlook on iPhone. Also I was able to add it to Apple Mail on iPhone.
Jeronimo Fuerte 46,845 Reputation points Independent Advisor

2026-10-15T02:34:44.8533333+00:00

Sorry to hear that you are having trouble with this situation. First, sign in to https://connect.xfinity.com using the affected account, navigate to Settings > Security, and verify that Third Party Access Security is enabled. This setting must be checked to allow applications such as Outlook to access the mailbox. Second, Comcast has been transitioning email accounts to Yahoo Mail throughout 2026. If this particular account has already migrated, you must configure it using Yahoo Mail authentication and server settings rather than the original Comcast settings. You can review the official information here: https://www.xfinity.com/support/articles/yahoo-email-migration-overview

Could you please confirm whether you can sign in to the affected account through Xfinity webmail, whether Third Party Access Security is enabled for that specific account, and whether you have received or accepted an invitation to migrate it to Yahoo Mail? Also, when the sign-in fails in New Outlook, does the error provide any additional troubleshooting details or an error code? This would help narrow down the cause without affecting your four working accounts.
Rejean Paquet 0 Reputation points

2026-10-15T15:46:06.94+00:00

I can logon to my Xfinity email using webmail, under setting/security Third Party Access Security is checked.

I never received an invitation to migrate to Yahoo. I have 3 other Xfinity emails and they work fine in Outlook.

When the sign in fails I get a popup window (see attached file Outlook6.jpg). Outlook6.jpg

I have 3 options (Troubleshooting-Continue-Advanced Setup)

If I choose Continue, I get prompted for the password.

If I choose Advanced Setup, then I get to choose Email provider, I select IMAP and we go again thru the same screens and same failure.

If I choose Troubleshooting I get another popup window (see attached file Outlook7.jpg)Outlook7.jpg

then I get 2 choices (Back or Troubleshooting details). If I click on Troubleshooting details then I go back to Outlook Your accounts. But on the side I get a smaller window where I can enter a note and attach a screenshot and submit, I assume it creates a trouble ticket similar to what I did (see attached photos Outlook8.jpg and Outlook9.jpg) Outlook8.jpg Outlook9.jpg

Hope this helps.

Your answer

Rejean Paquet 0 Reputation points

2026-10-14T22:28:50.5233333+00:00

I renamed OLK and OneAuth folders, the I restarted Outlook, I had to re-add 4 accounts, they all working fine. One failed, the same I am having problem before = ******@comcast.net. Like I said, I was able to add it to Outlook on iPhone. Also I was able to add it to Apple Mail on iPhone.
Jeronimo Fuerte 46,845 Reputation points Independent Advisor

2026-10-15T02:34:44.8533333+00:00

Sorry to hear that you are having trouble with this situation. First, sign in to https://connect.xfinity.com using the affected account, navigate to Settings > Security, and verify that Third Party Access Security is enabled. This setting must be checked to allow applications such as Outlook to access the mailbox. Second, Comcast has been transitioning email accounts to Yahoo Mail throughout 2026. If this particular account has already migrated, you must configure it using Yahoo Mail authentication and server settings rather than the original Comcast settings. You can review the official information here: https://www.xfinity.com/support/articles/yahoo-email-migration-overview

Could you please confirm whether you can sign in to the affected account through Xfinity webmail, whether Third Party Access Security is enabled for that specific account, and whether you have received or accepted an invitation to migrate it to Yahoo Mail? Also, when the sign-in fails in New Outlook, does the error provide any additional troubleshooting details or an error code? This would help narrow down the cause without affecting your four working accounts.
Rejean Paquet 0 Reputation points

2026-10-15T15:46:06.94+00:00

I can logon to my Xfinity email using webmail, under setting/security Third Party Access Security is checked.

I never received an invitation to migrate to Yahoo. I have 3 other Xfinity emails and they work fine in Outlook.

When the sign in fails I get a popup window (see attached file Outlook6.jpg). Outlook6.jpg

I have 3 options (Troubleshooting-Continue-Advanced Setup)

If I choose Continue, I get prompted for the password.

If I choose Advanced Setup, then I get to choose Email provider, I select IMAP and we go again thru the same screens and same failure.

If I choose Troubleshooting I get another popup window (see attached file Outlook7.jpg)Outlook7.jpg

then I get 2 choices (Back or Troubleshooting details). If I click on Troubleshooting details then I go back to Outlook Your accounts. But on the side I get a smaller window where I can enter a note and attach a screenshot and submit, I assume it creates a trouble ticket similar to what I did (see attached photos Outlook8.jpg and Outlook9.jpg) Outlook8.jpg Outlook9.jpg

Hope this helps.