[Mailman-Users] subscribers bouncing

[Debbie]

I checked the archives and didn't find what I was looking for, so please 
forgive me if this has been answered already.
I keep having about 90% of my 3000 subscribers bouncing on a regular basis. 
I've checked and most are good addresses. Even the address that I use keeps 
bouncing, and sending me the bounce message, even though I get all the 
messages I send.
 Have I done something wrong? Does it have something to do with it being an 
annoucement list?
It's getting to be an awful lot of work to manually contact the bounced 
subscribers to make sure they are still online and then to take the bounce 
off of their account. Only to have to go through it a few weeks later and do 
it again.
Can anyone help me?
Thanks in advance,
Debbie