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5.1.0 Authentication required

  • 2 replies
  • 1 has this problem
  • 14 views
  • Last reply by rbharlan

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Many users have had issues with this failure of emails to be sent. All seem to apply to all outgoing emails. I have occasional problems with only some emails. I have checked Thunderbird settings on the outgoing server (SMPT). They show correct user name and show authentication method: Normal password.

I have noticed that the isp password in windows 10, under settings - accounts-email-email& accounts shows a hidden password with too many dots for my current password, but I don't use any windows mail.

Where is the password stored that TB uses for authentication? Is there a way to confirm an exact reason for these emails to be rejected? My current problem is with a website in Europe.

Many users have had issues with this failure of emails to be sent. All seem to apply to all outgoing emails. I have occasional problems with only some emails. I have checked Thunderbird settings on the outgoing server (SMPT). They show correct user name and show authentication method: Normal password. I have noticed that the isp password in windows 10, under settings - accounts-email-email& accounts shows a hidden password with too many dots for my current password, but I don't use any windows mail. Where is the password stored that TB uses for authentication? Is there a way to confirm an exact reason for these emails to be rejected? My current problem is with a website in Europe.

All Replies (2)

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Thanks for showing how to see and manage passwords in Thunderbird. All of the passwords are correct, so that eliminates any problem with passwords. I don't know where to go from here. The problem persists with one email address.