I was using Thunderbird (15 or 24, turned out not to matter) as my email program on Windows 7. I had been using it without problems. I changed my password on Hotmail, and suddenly Thunderbird was no longer able to download messages from Hotmail. Instead, I joined others who started getting this error message:
Sending of password did not succeed. Mail server pop-mail.outlook.com responded: authentication failed
I got that particular message because I had taken Microsoft’s advice to replace my original “pop3.live.com” server (in Thunderbird account settings; outgoing server smtp.live.com) with this pop-mail.outlook.com alternative. Previously (for those who are searching for that alternative) the message was
Sending of password did not succeed. Mail server pop3.live.com responded: authentication failed
When I clicked OK on that dialog, Thunderbird said this:
Login to server pop-mail.outlook.com failed.
Login to server pop3.live.com failed.
If I clicked “Retry” or “Enter New Password,” I would just get that dialog over again. If I clicked Cancel and then went into Thunderbird’s Tools > Options > Security > Passwords tab > Saved Passwords > Show Passwords, I could see that it had the right password. At first, I saw it was saving the password with the previous pop3 setting, but removing that entry and retrying didn’t change anything; the message would come back all the same.
To fix this, I tried everything. I moved my profile and various Thunderbird files around; I created a new profile; I uninstalled and reinstalled Thunderbird. I saw that the thing hadn’t completely uninstalled, so I followed advice on how to really uninstall Thunderbird. I made sure I wasn’t using a password longer than 16 characters; I changed passwords; then I changed again to a password consisting solely of alphanumeric characters. I rebooted, did Windows Update, ran registry cleaning utilities, rebooted again, etc. After wasting hours with nothing accomplished other than some scrambling of my saved emails, I gave up, bit the bullet, and tried installing Outlook as an alternative email client.
Then an odd thing happened: I was also unable to get Outlook to accept my Hotmail account name and password. It appeared that the problem might not be with Thunderbird alone. Then again, it wasn’t exactly a problem with Hotmail per se; I was still able to log into Hotmail.com (actually, mail.live.com) on my web browser. It seemed, rather, to be a matter of the interface, somehow, between Hotmail.com and the email client program.
One site said that it could be a problem if my email program was checking for new messages more than once every ten minutes. I went into Tools > Account Settings > Hotmail Server Settings and changed it from the default “Check for new messages every 1 minutes” to be 10 minutes instead. I gave it an hour, but no joy: Thunderbird had still not downloaded the messages that I could see sitting in my Hotmail Inbox on the web browser, and File > Get New Messages For > Hotmail still gave me the same error message. Anyway, I would think I would get the error message
The STAT command did not succeed. Error getting message number and sizes. Mail server pop3.live.com responded: Exceeded the login limit for a 15 minute period. Reduce the frequency of requests to the POP3 server.
if I were really overdoing it. So that didn’t seem to be the explanation. Taking another suggestion, I downloaded and ran the portable version of Thunderbird. But when I got to the point of configuring the Hotmail account, upon clicking the “Done” button, I got the same error I had seen before:
Configuration could not be verified — is the username or password wrong?
A search on that message led nowhere in particular. Looking at the dialog containing that error, once again I clicked on the Advanced Config button, but that just took me to the same old Settings dialog. Someone suggested turning off my antivirus program’s scanning of incoming email messages, but that made no difference.
A thread made me wonder whether the problem was that I had set up two-step verification on Hotmail. I had kind of forgotten about that. In the Hotmail webpage in my browser, I went into the settings icon (shaped like a gear) > Options > Account Details > Edit security info > Turn off two-step verification. (In the more recent version of Hotmail, I think the sequence would begin with Settings (gear) > Options > Security & privacy > More security settings > Obtain and enter a code if required.)
And, wow. That was it. That was the problem. Email messsages immediately came cascading into my T-bird inbox. Problem solved!
Note: subsequent discussion (see Comments, below) indicates that Hotmail may offer some users another approach.