If your problem is with Mozilla Thunderbird, see this forum for support. https://support.mozillamessaging.com/.../home
or this one
http://forums.mozillazine.org/viewforum.php?f=39

I am not using Mozilla thunderbird. I am using Mozilla Firefox. Please advise

I received an email from HOTMAIL as below telling me to change the email client server to leave email message on the server. Now all emails that I reply from my blackberry device cannot be seen in Sent Folder when I open the hotmail account by using desktop computer.

How to change the server option? in what menu? I cannot find in Mozilla's Tool menu. Thank you for helping me sorting out this problem.

Email from Hotmail as below: If you use an email client (e.g. Microsoft(R) Outlook(R), Mozilla(R) Thunderbird(TM), etc.) to access your aquos9@hotmail.com messages, change your email client settings to leave your email messages on the server. If the email client does not leave email messages on the server, the BlackBerry(R) Internet Service may not be able to deliver them to your BlackBerry(R) device.

To leave email messages on your email server you may need to complete the following steps:

1. In your email client (Outlook, Thunderbird, etc.) on your computer, under Tools or Mail > Preferences.

2. Select your email account.

3. Locate advanced, server settings or options.

4. Select the option to leave email messages on the server.

Refer to your email client help for more information.

The Mozilla Firefox is a web browser and not email client as to why there is no such settings in Tools menu in Firefox.

Please update to Firefox 18.0.2 ASAP Update Firefox to the latest release