Help > Troubleshoot Mode better?

Thanks for the suggestion. I did it, but that did not solve my problem. So I conclude addons not a factor. I have not intentionally installed any addons but gather that this can happen without user action.

How can I tell if I have exited troubleshoot mode? I restarted firefox and also Thunderbird.

re : to multiple recipients

How are these 'multiple recipients' added ? For example... In Write message window:

1. Do you use the 'Contacts Sidebar' to select various names and then click on eg: 'Add to Cc' button ?
2. Do you start typing name in 'TO' field and select from the auto suggestion list?
3. Do you have contacts in a 'Mailing List', so you select the 'Mailing List' name (meaning individual contacts not shown)?
4. OR do you open Address Book - Select 'Mailing List' name and then click on 'Write', so all contacts are added individually into a TO field ?

When you add the contacts, which one of the following are you using - TO or Cc or Bcc? If Bcc, are you putting anything in a TO field or is it empty ? Suggest you always put one email address in a TO field even if it is your own.

How many recipients are you talking about? 3 or 30 or 60 etc ?

If you use a 'Mailing List': Are you certain that all the contacts in that Mailing List do have valid and correct email addresses because if any contact in a Mailing List does not have a valid email address then it will not send.

I made it as simple as possible. Started typing email address and clicked enter when the suggested auto-complete appeared.

I've been using Thunderbird, and this method, for several years. Here's some TBird "troubleshooting info"

User Agent Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.6.1 OS Windows_NT 10.0 19044 Application Binary C:\Program Files (x86)\Mozilla Thunderbird\thunderbird.exe

Who is the mail provider?

https://support.mozilla.org/en-US/questions/1368097

https://support.mozilla.org/en-US/questions/1367576

Access info and post data. Menu app icon > Help > More Troubleshooting Information Under 'Mail and News Accounts' section Copy all the information and paste it info this forum question OR Post and image showing the details of the 'Mail and News Accounts' section

Hope you can decipher this without the grid!

ID Incoming server Outgoing servers Name Connection security Authentication method Name Connection security Authentication method Default? account1 (imap) imap.nsvc.us:143 None Normal password smtp.ipage.com:587 None Normal password true account2 (none) Local Folders None Normal password

Appreciate your handle

Hope you can decipher this without the grid! ID Incoming server Outgoing servers Name Connection security Authentication method Name Connection security Authentication method Default? account1 (imap) imap.nsvc.us:143 None Normal password smtp.ipage.com:587 None Normal password true account2 (none) Local Folders None Normal password

Try it with secure settings for the ipage server:

https://support.mozilla.org/en-US/questions/1368097#answer-1483919

You're beyond what I can do. I don't think I use iPage. Calling in my helpdesk provider who set up my Thunderbird. One question though: does the fact that I can send the same message from Roundcube (webmail provided by Fat Cow) clear them from the issue or not?

Tools/Account Settings, Outgoing Server (SMTP) at the bottom of the left pane, Edit the iPage server, change the connection security to SSL/TLS and the port to 465, authentication method to 'normal password'.

Sending from webmail is a different process than sending through an smtp server with a mail client. But using non-secure smtp settings might not allow sending to multiple contacts.

I was able to do. No change. I restarted Tbird (is that necessary?) and the email still won't go.