KenMr said

I have created lists within my address book of varying sizes and I expected that I enter the list name in the Send To entry field, and that would send to everyone in the list. It doesn't.

I also tried copying the entries in one of my lists to the Send to filed, but Thunderbird complains about non ASCII characters (the < & > within the email address entry) in the addressee lists.

How did you populate your Mailing Lists?

I had created a list, then added email addresses to the list by dragging them across to it from my main address book. That appeared to be working OK. I think I've discovered that that bit was OK, but the group email creation was incorrect. I was trying to use the list name, rather than create an email from the address book, select list, click Write button in list window. THAT works! Only issue is now: how can I create email with BCC on all the addressees? Some of the lists are long and its a bit of a chore to change each. Zenos, thanks for quick response.

Do it via a new 'Write message and use the 'Contacts sidebar to select the address book. the mailing list will be included in the list of contacts dispalyed. select the mailing list name and click on 'Addto Bcc'

• https://support.mozilla.org/en-US/kb/how-create-and-use-mailing-lists-thunderbird

Mailing lists depend upon the contact information being up to date, so the contacts must have an email address in the 'Email' field.

Unfortunately when I use this method I get: B Road <"B Road"> is not a valid email address because it is not of the form user@host. You must correct it before sending the email. B Road is the name of my list for that road and contains a number of email addresses. Thanks for the help so far!

In the past, I have come across a few of these weird quirks, so could you try the following to see which if any seem to work best.

To rename a mailing list select mailing list, click on 'Properties'

1. Sometimes, it does not like more than one capital letter, but will allow a capital letter at the start eg: rename the mailing list so it says: B road

2. Sometimes it does not like a space, so try both of these options, just in case it is a space and a capital letter: B-Road and B-road

Please report back on what results you get for each of these variations.

It looks like you're right Toad-Hall, just an email with a list that I created, a name with no spaces. Regrettably I can't use one of the other lists, as I don't want to surprise my correspondents with drivel or test messages! I've used properties to reanme them without spaces, so it will be interesting to see if that works with the existing lists. Thanks for the suggestion