Try to rebuild the index file of the troubled folder.

Right-click the folder - Properties - Repair Folder

Thanks, tried that and it eliminated about 800 emails from my inbox folder. Thank goodness for mozbackup. what is interesting is if i had a reply to the message, the reply is there and shows the original email. if i had not had a reply the email is blank.

tried that and it eliminated about 800 emails from my inbox folder.

It appears your mail file(s) were corrupt. Anti-virus software is most likely the culprit.

Create an exception in your anti-virus software for the Thunderbird profile folder, so that the anti-virus real-time scanner will not scan it. http://kb.mozillazine.org/Profile_folder_-_Thunderbird

Don't let your anti-virus software scan incoming and outgoing messages.

Don't let your anti-virus software scan attachments.

Don't let your anti-virus software intercept your secure connection to the server.

Remove any add-ons your anti-virus software may have installed in Thunderbird.

Keep it working. http://kb.mozillazine.org/Keep_it_working_-_Thunderbird

And last but not least, backup your Thunderbird profile on a regular basis. https://support.mozilla.org/kb/profiles-where-thunderbird-stores-user-data#w_backing-up-a-profile