Tell us what domain is in your email, such as outlook.com, hotmail.com, etc., and we will try to assist. Generally, it is much easier than it seems.

Hi David I have a hotmail.co.uk account, an outlook.com account and a gmail.com account

The gmail account is not affected, as Microsoft has no interest in that. Here is the Microsoft link from that email: https://support.microsoft.com/en-us/office/modern-authentication-methods-now-needed-to-continue-syncing-outlook-email-in-non-microsoft-email-apps-c5d65390-9676-4763-b41f-d7986499a90d

It states to change authentication of incoming server settings to OAUTH2 And to change outgoing server to smtp.office365.com, STARTTLS, port 587 and OAUTH2

Try the above and let us know.

Hi I managed to change the settings for each of the 3 accounts for step one. However, when I try to change the outgoing details (point 2.d) , there is no Oauth2 option. Where am I going wrong?

Puzzling. Try closing and restarting thunderbird and attempt again, and post screenshot of the SMTP server pane for the account.

Closed TB and tried again. no luck. Sorry for delay - had to google to find out how to take sceenshot and then again where to find it.

wont this screenshot become public and therefore means others can access my email account?

Your account is safe, just don't post password. This is puzzling. At the Outgoing Server (SMTP) server pane, try creating a new SMTP server with same setup and see if OAUTH2 is allowed. If so, delete the current one and check on account pane to verify that the bottom line with SMTP link is pointed correctly.

Not allowed. And didnt understand the 'if so...' statement. Sorry

A minor item: be sure that settings>privacy&security has 'accept cookies' box checked. I will also see if someone with more technical expertise can advise. this is usully straightforward.

Thanks David. Have checked and am set up to accept cookies. Much appreciate your help and support and grateful you are hanging in there! I'm going to take a break from the PC for a little while and have something to eat. In the meantime, will the changes that I have made still allow everything to work ok? And just in case it is relevant, entering office365 - I'm not on that version of microsoft but an earlier one (albeit with updates).

I believe all should work, as the cutoff is in September. And don't worry about the office365 title. I don't even use office, but that's the name that Microsoft uses. A tip: at https://www.bluefive.pairsite.com/ is a small FREE screenshot utility called snapshot that I like. It's small, much easier to use that the windows approach (in my opinion).

Just tried a test email and it saying that my authentication method is wrong. Now I cannot send or receive on hotmail nor outlook. I can send from gmail but neither outlook nor hotmail will receive it. Tried to use the link the to photo screen the message but my PC is blocking access as non secure

You have an outlook.com account and a hotmail account, but there are 4 outlook smtp servers. Delete all of them except the ones for the 2 MS accounts, and then make sure your BrianHenryHome account is set to send on the Default smtp (select the account in the left pane of Account Settings, set the smtp in the right pane's Outgoing Server (SMTP) drop-down). Repeat for the hotmail account. The smtp settings for the 2 accounts should be the same except for the User Name (email address).

If you have the current release 115, and the smtp is smtp.office365.com, 587, STARTTLS, you should be able to select OAuth2 in the authentication drop-down, but if not, there is a way to force it:

https://support.mozilla.org/en-US/questions/1451090#answer-1659631

Check also that the incoming server is outlook.office365.com, 993, SSL/TLS, OAuth2, email address.

Hi Sorry but try as I might I do not understand this. How and where will I find the right ones to delete and which to delete? And I have no idea what 115 release is.

And what should the port numbers be?

@sfhowes was identifying that you have four SMTP servers, yet you indicated only two accounts. To get rid of the clutter, change the description field for each to something unique, even if it's just ONE, TWO, THREE, FOUR. Then, click the account panes to see to which each is linked in the bottom line SMTP link, where you will see one of those four numbers. After verifying both, you can delete the other two. Problem not solved, but the clutter is gone.

The ports are 993 for input ff IMAP, and 995 if POP, and 587 for output.

If the OAUTH2 option is not shown, @sfhowes showed a link to a means to fix that. The text for the fix is: I don't know why OAuth2 doesn't appear in the drop-down, as it does in my setup. Open Config. editor from Settings/General and type mail.smtpserver.smtp1.authMethod in the search box (or change 1 to 2 or 3 to correspond to the outlook account (mail.server.server1.name displays the hostname of server 1). Edit mail.smtpserver.smtp1.authMethod and change the value to 10, then see if OAuth2 appears in the Account Settings.

The above sounds complex, but it is rather simple, once you do it.

Hi David It certainly sounds impossibly complex to me but I will try after a good nights sleep (I hope). I do appreciate both of your efforts to resolve this for me. Thank you. I will respond tomorrow. Brian

Hi

I am doing my best even though it appears to be not good enough! Have followed all instructions but when trying to send message I'm getting:

Sending of the message failed. The message could not be sent because connecting to Outgoing server (SMTP) smtp-365office.com failed. The server may be unavailable or is refusing SMTP connections. Please verify that your Outgoing server (SMTP) settings are correct and try again.

Further, two of my email accounts are using the same server and when I try to correct the user name on one, it automatically alters the other.

PS I corrected the above typo in 365 office but it has not made any difference