What were you using previously which supposedly worked better? Maybe it used a filter for messages not expressly addressed to you.

If you don't see your own email address in the message's header then it's likely it had your email address as a Bcc: ("Blind Carbon Copy").

Filters are a poor way to handle Junk. I certainly don't have as many as 100 email filters (what I do have are in the majority just for automated filing) and I've been using Thunderbird for many years. Filters simply aren't effective, in the long term, though there are occasional spam campaigns or scams which can be filtered, but it's an inefficient and continual catch-up game to do it with filters. Mark your bad stuff as Junk, and keep doing so. If you see good messages marked as Junk then mark them as Not Junk.

DON'T SEE ANY OTHER WAY TO HANDLE ALL THE JUNK. HAVE USED WINDOWS LIVE MAIL AND CENTURYLINK WEB MAIL BOTH WITH NO JUNK PROBLEMS. AGREE THAT FILTERS ARE A POOR WAY TO HANDLE JUNK. MANY TIMES THE EMAILS HAVE NO JUNK BUTTON TO USE AND SINCE THEY HAVE NO EMAIL ADDRESS IN THEM , NO PLACE FOR A FILTER. IS THERE A WAY FOR THUNDERBIRD TO FILTER MESSAGES NOT EXPRESSLY ADDRESSED TO ME?

You don't have any way of keeping up. If you open the spam the sender may be notified that you are a valid email address. I have my third-party cookies set to "always", but keep until is set to "ask me every time". That way I get a chance to reject them. Turning them off altogether can be problematic. Don't open any emails If you don't recognize from the subject line that it's something you authorized. Drag it to a file for suspicious emails. I don't use junk or trash for this. It's too easy to loose something that you later find out wasn't junk if your in the habit of emptying those folders. If it's from a friend or you requested emails from companies, Macy's, Starbucks, etc., then create a filter to move them to a folder of your choice. As the emails come in they'll be sent to those folders. That would leave only "junk" in the inbox. Thunderbird catches most of the spam and blocks remote content from loading which prevents the email from sending your personal data to the sender, but nothings perfect. The main thing the spammers want is to find out if they have stumbled onto a valid email address. If you open one, what ever you do, don't ask them to take you off there mailing list. Your address will be for sale on the black market before you can say oops. By not opening up or responding to them in any way they will assume there's no one there and after a while the messages will stop. It took about a year for mine to go away altogether, well most. The up side of this is you will have a nice file folder system in place. Friends, business, shopping, etc., and you can quickly spot the emails you want to read right away.

Some service providers have spam filters but you have to be watchful.   One of my brothers emails got caught in it. I turned off that filter. I prefer to be the gate keeper, but I don't recommend it for anyone who doesn't approach all there emails with a lot of suspicion. Of course you need virus protection. Mine reads every email that comes in and deletes any with a virus. Emails with viruses in them are not the same thing as one with spam, so make sure your protected. I hope this helps.

The end of my last entry appears to have gone over the limit. Here is the text as I wanted you to see it. Some service providers have spam filters but you have to be watchful. One of my brothers emails got caught in it. I turned off that filter. I prefer to be the gate keeper, but I don't recommend it for anyone who doesn't approach all there emails with a lot of suspicion. Of course you need virus protection. Mine reads every email that comes in and deletes any with a virus. Emails with viruses in them are not the same thing as one with spam, so make sure your protected. I hope this helps.

I do not open or did not open any of the junk emails-am well aware of getting on a list and no way of getting off! Dropped all my message filters-you are right -no way to keep up let alone get ahead. Just keep marking the junk as junk using either the junk button or the letter j -found it in the help section. So for now I believe I am ok-thanks for direction.

I have a filter action for "isn't in my address book", so I'd try:

a) create a new address book containing your own email addresses; let's call it the "me address book"

b) create a filter using:

rule: "to" "isn't in my address book" "me address book"

action: "delete" (but I'd try something less drastic first, such as adding a tag or star or moving it to a folder, until we're sure it does as we expect.)

If you don't have the "isn't in my address book" option then maybe you need the JunQuilla add-on.