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Cannot receive emails, thunderbird is rejecting password and sending pop-up windows. How do we correct this?

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  • 2 have this problem
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  • Last reply by Ryan W

FArturi
FArturi
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Whenever I go to receive emails, a window pops up stating, "Sending of password for user fsa5 did not succeed. Mail server pop.optonline.net responded: Authentication failed". I have repeatedly entered my master password in but the program rejects it. I have been unable to receive important emails for 2 days and cannot continue to experience this problem.

Whenever I go to receive emails, a window pops up stating, "Sending of password for user fsa5 did not succeed. Mail server pop.optonline.net responded: Authentication failed". I have repeatedly entered my master password in but the program rejects it. I have been unable to receive important emails for 2 days and cannot continue to experience this problem.

All Replies (1)

Ryan W
Ryan W
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To diagnose problems with Thunderbird, try one of the following:

  • Restart Thunderbird with add-ons disabled (Thunderbird Safe Mode). On the Help menu, click on "Restart with Add-ons Disabled". If Thunderbird works like normal, there is an Add-on or Theme interfering with normal operations. You will need to re-enable add-ons one at a time until you locate the offender.
  • Restart the operating system in safe mode with Networking. This loads only the very basics needed to start your computer while enabling an Internet connection. Click on your operating system for instructions on how to start in safe mode: Windows 8, Windows 7, Windows Vista, Windows XP, OSX
If safe mode for the operating system fixes the issue, there's other software in your computer that's causing problems. Possibilities include but not limited to: AV scanning, virus/malware, background downloads such as program updates.