Support for what? This forum is the support for using Thunderbird email client. Post details of your issues and if a volunteer has any ideas they will help.

Your email provider will have support for their email system if you need that. Contact them for help with their email system.

Hi elite5, Thunderbird support is provided using this public forum. The people that answer questions here are users just like you, volunteering their time.

If you're unable to send messages, could you please try the solutions in the following article, and see if any of them help: Cannot send messages

If you're still unable to send messages, we'll need more information about your setup and what you're seeing when you try to send a message.