getting that account on your phone perhaps?

I don't have Thunderbird on my phone and that account is set up as a pop account on my phone so I don't think that is the issue. This is a new laptop in the last month. Thunderbird worked as it should on my old laptop regarding read/unread.

And was your old laptop configured as POP and your new one as IMAP. My guess is yes.

Matt said

And was your old laptop configured as POP and your new one as IMAP. My guess is yes.

Hmmm, I'm not sure. It's possible that I had the old one as pop or I may have changed it before I got my new laptop. I know it started out as pop. The new one is imap.

I was just in Thunderbird. I highlighted (chose/selected) the inbox for my isp email account and was looking at it when an email appeared. I did nothing and the message changed to "read" after about 3 seconds.

In those three seconds your phone will have downloaded the mail and marked it as read.

Try turning OFF the phone and getting a couple of mails, then turn on the phone and let it get mail. Watch Thunderbird and I would think you will see the mails it downloads turn to read as it happens.

Thanks for your help. They were changing to read from the phone and/or my desktop. I changed my isp email back to pop. Not the perfect solution but solved my read/unread problem.

One more question though. Why weren't my hotmail and gmail messages being marked as read when my isp emails were marked as read?

Thanks again, Steve

that would depend on the setting in the phone and the actual server software. Some server software marks messages read upon download to make other applications including their own web mail look better. It may even be that your ISP has setting on their web site to mark messages read or not on download. Contrary to popular belief, email is complicated.