http://kb.mozillazine.org/Thunderbird_:_FAQs_:_Create_Mailing_List#Avoid_sending_to_an_address_in_a_mailing_list

I want to send a message to one of my group but after I have added this group, I want to go into the group and remove one of the email addresses in that group before I send the message.

Did you check the article and the add-on mentioned there?

When I tried to download the add on I received the following: Cannot open - not compatible with thunderbird 24.3.0

First, make sure you're installing the add-on in TB, not Firefox.

http://chrisramsden.vfast.co.uk/3_How_to_install_Add-ons_in_Thunderbird.html

Second, if you receive a 'not compatible' error, install this add-on before you install the 2nd one:

https://addons.mozilla.org/en-US/thunderbird/addon/checkcompatibility/

It seems to but it looks like if I want to forward a message to two different groups, I will need to send two separate messages one for each group and the address of each person that I do not want to forward the message to for each group/message.

With AddExpandedList, Forward a message, press F9 to show the Contacts sidebar, right-click a mailing list, 'Add to (To, CC or Bcc) field with expanded lists', repeat for other mailing lists, then delete whichever contacts you like from the To, CC or Bcc lines. One message to multiple expanded lists.

When I right click the message that I want to forward it come up as Unicode (utf-8) and it will not allow me to enter anything into the contact or change the subject. When do I press F9 and being as I never use the f keys do I press the shift or ctrl or fn or alt prior to pressing F9?

The F9 key by itself should work on normal keyboards. Or, select View/Contacts sidebar in a Write window (press Alt if the Menu Bar is hidden).

So, when you right-click a message and select Forward from the context menu, you can't enter anything in the To: box or change the Subject? That is very unusual, and suggests something is wrong with your profile folder. Does that happen if you run in safe mode? Hold Shift (Mac:Option) when you launch TB.

I held the shift key down and opened it in safe mode and when I right clicked an email it will allow me to forward and it will let me double click one of my groups called family but when the curser moved to the next line and I double click on friends to add it, it does not add the second group it just changes the first line to friends and deleted the other group. Also if I go the group and double click, it does not allow me to remove any one, it just turns blue. Should I give you my phone number so we can work on this?

There's still something wrong, since you should be able to double-click one mailing list after another in Contacts sidebar and have them added to separate address lines.

I'm afraid telephone support is not possible, but you should post your troubleshooting information so we can possibly diagnose the problem:

select Help/Troubleshooting Information, click 'Copy text to clipboard', paste (Ctrl-V) the text in a reply box, delete any of the printer and font info.

https://support.mozilla.org/en-US/kb/ask-tb#w_how-to-ask-your-question

Never mind I will just have to find another software to read my mail.

I think the first address you entered has just scrolled up out of sight when you add the second. If you hover your mouse/cursor over the address box it should present a tooltip-like pop-up window listing the entered addresses.

You can enlarge the space allocated to addresses by dragging the top edge of the message text window downwards.