What server are you talking about ? Is this a outlook/hotmail/live/msn account or an account that uses microsoft office server ?

Our server is from the company, Always Web Hosting.

Server Settings according to 'always hosting'. * https://portal.alwayswebhosting.com/index.php?rp=/knowledgebase/33/How-do-I-setup-my-mail-to-use-SSL.html ''Set your mail server to the server's host name for SMTP/POP3/IMAP (instead of mail.yourdomain.com) and then make sure that your mail client is using the following ports for SSL:'' ''* SMTP - 465'' ''* POP3 - 995'' ''* IMAP - 993'' ''As always you want to make sure that your account name is user@domain.com (or user+domain.com) and that you are using authentication on your SMTP server.'' ''(If you do not know your server's SSL hostname, you can see it by logging in to cPanel and then logging at the address bar. It is in the form of: server#.sslpage.com such as server3.sslpage.com)'' '''Pop''' * Server name: server's host name (instead of mail.yourdomain.com) * Port: 995 * Connection SEcurity : SSL/TLS * Authentication Method: Normal Password * User name : full email address * Password: same one used to access webmail account '''IMAP''' * Server name: server's host name (instead of mail.yourdomain.com) * Port: 993 * Connection SEcurity : SSL/TLS * Authentication Method: Normal Password * User name : full email address * Password: same one used to access webmail account '''SMTP''' * Server name: server's host name (instead of mail.yourdomain.com) * Port: 465 * Connection SEcurity : SSL/TLS * Authentication Method: Normal Password * User name : full email address * Password: same one used to access webmail account First check you really are using the correct server settings in Thunderbird. See above. Some people alter the smtp port to 25 whilst travelling, but many servers may block port 25. That's why it's best to use webmail whilst travelling. When logged directly onto webmail account you are by passing the SMTP used by third party email clients. You cannot compare webmail with any third party email client. However, if you can access webmail account then it proves you know the password. Emails get stopped by server if using wrong server settings or server says password is incorrect. Server may also block sending if it's own smtp server spam filter does not like the email. If Thunderbird is set up to save passwords then check the correct password is actually set correctly. In Thunderbird * Settings > Privacy & Security * Scroll down to Password section * Click on 'Saved Passwords' * Click on 'Show Passwords' * If asked for a password - when you start up computer and you enter a password to access desktop etc - that is the password required. * You should see two lines for the account - incoming and smtp outgoing. If you are getting mail OK then you know that password is stored correctly. * Right click on the smtp:// line and select 'Edit Password' * clear all contents and retype the correct password. * click on 'Close' You mention "I recently came back from being abroad to find out I am not able to send emails from my MAC computer." Whilst abroad - did you take your MAC computer with you ? Whilst abroad did you access email via webmail or Thunderbird ? It's possible the server has been detecting you have been using different IP addresses in your travels and now thinks you may not be you - in which case it puts a block on the account. Some MAC computers auto detect where they are located so using correct 'Timezone' for location. Suggest you check out whether computer has properly reset timezone for being 'home'. If you are using a VPN on MAC computer then switch it off because most servers do not like anything that tries to hide the IP address, so they just block access. You may also have issues if your computer Anti-Virus product has control over Firewall and it's blocking access to the port used by Thunderbird. * Exit Thunderbird * Access Firewall * Set up Thunderbird program as an allowed program. When it does not send, what happens ? What error message do you get? Please tell what the error message says word for word or upolad an image showing it.