Check your email account at the online site of email provider to see if photo was received to the account.

Checked email provider on line. The photos are not there. I am thinking of changing back to a previous version of Thunderbird mail where I was able to send photos from my cell phone to my email.

If you send photos from phone, from what you are saying, the photos are not reaching the account. Thunderbird has no involvement in that. Thunderbird sees the messages/photos only after they reach the account. The problem is in your phone.

My thinking is that this newer version of Thunderbird must have some security measures that are preventing the photos from getting through. I have searched all of the account settings and cannot figure out what it might be. That is why I am thinking of going back to a previous version of Thunderbird to see if that solves the problem. Thank you for your help.

Please understand about the network. The phone sends the message to your email server, not to Thunderbird. If the photo doesn't reach the email server, Thunderbird can do nothing. I wish you well in this. I suggest you log on to the web interface and then send a photo from your phone to see what happens.