I also have this problem. I attempted to uninstall and reinstall Thunderbird, but it made no difference and still does not function.

TB doesn't use a Spam folder. 'Spam' is where the mail provider places unwanted messages, whereas TB places it in the Junk folder - if you have TB's junk controls in force. Access the account through the webmail interface and examine the spam rules.

The Spam folder may also be used by some 3rd-party security programs, which often update, and sometimes become inoperable.

Excuse me for my poor terminology, I call any junk mail spam. I am referring to Thunderbirds junk filter. I have junk controls in force, but they stopped working and when I run the junk filters they do not filter anything. Likewise anything that I flag as junk does not get remembered as junk.

Have you tried resetting the junk data in Tools/Options/Security/Junk?

http://kb.mozillazine.org/Junk_Mail_Controls

Yes, along with reinstalling, no mail is automatically placed into the Junk folder by Thunderbird.

Oh how annoying that it doesn't work for you either.. :( Before, I just right clicked on an email address when I had the email up and then "Create filter rules" (the option at the bottom in the drop down meny). And then every time when I got an email from that person / store it ended up in the trash or where I had chosen that they would end up, now it doesn't work at all. So annoying and they make me so sad. Can someone please help meeee, everytime i open my email I have like 400 hundred emails that I have to delete one by one..

It will be so hard for me if I should change email address, I will not remember all the importen place to change email, or do you think I should just change email program? It should be easiest huh?