The filters I'm referring to might be spam filters that work on the Yahoo side and move some messages to Spam, while the AT&T filters do not. If that is the case, you probably can't disable the filters on Yahoo, but you should be able to whitelist specific messages or senders.

Do you have the POP account set to leave mail on the server after download or delete after download? Is the account set up in TB as POP on the AT&T servers as well as on the Yahoo servers? I would think that could cause problems with missing mail.

Ok I get that. I can go into the spam folder and mark them not junk or not spam. I will try that. Both accounts are set as pop as they are set up that way by AT&T and yahoo. I always have set up my accounts to not leave mail on the server. Not sure if that is the problem. I put the AT&T accounts back on Thunderbird just to check if the mail was in there that was missing and it is there. For some reason, they are still going to the ATT version of the yahoo account. Would leaving the mail on the server fix my problem?

If you have it set to delete from the server with either account, then the account that downloads after the other will not have the same messages to download. If you must have a POP setup, then you should definitely 'leave on server' while you have the two setups active.

Last night, I changed everything over to be left on the server. This morning the two accounts (AT&T and Yahoo) which are the same ones both had 24 identical emails in them. Since this happened, I deleted the AT&T account so I feel this has been taken care of. I have been going into the web page mail and marking some of the spam emails not junk also. I will wait a couple of days and when everything is going well, I will close out this as problem solved. Thank you for your help.

Everything is going good except for this error message I get occasionally that I attached. This is the only thing I have left to figure out what it means.

I don't know why you still get an error about inbound.att.net, as I thought you had changed all att servers to Yahoo. Check if there is an account or identity or calendar still referring to that server.

Oh, I'm sorry. I did keep my husbands sbcglobal account for now because he switched to a gmail account and just wanted to make sure I changed all the email addresses in his important emails. Once I see nothing more comes into the sbc address that I forgot to change, I will delete that account. Just don't know why I am getting that error.

Maybe the error is appearing for the same reason this topic was started: the sbcglobal account isn't using a secure mail key that is now required by AT&T.

OK, well I will just deal with it as I will be deleting that account as soon as I'm sure I changed the email addresses over. Thank you for all your help.