I am using 1.2.9 w/ latest versions of php, mysql, apache. Zenphoto will not send mail out via comments or contact us form. I have tried just using the sendmail plugin and recieve the error below.

zenphoto_sendmail failed to send test (The Soupene Gallery) to one or more recipients

I also enabled the PHPMailer and selected the sendmail option and I receive the following error message when I try the contact us form.

zenphoto_sendmail failed to send test (The Soupene Gallery) to one or more recipients.
PHPMailer failed to send test (The Soupene Gallery). ErrorInfo:Language string failed to load: execute/usr/sbin/sendmail

I have looked thru all the logs that I know of and see nothing. Cox is my ISP and they do block port 25; could that be my problem? If so any suggestions on how to work around this. Thanks once again in advance!

Most likely, this is a problem for your host to fix. I would assume that either sendmail is not configured correctly or that blocking port 25 is, in fact, the problem (assuming that the SMTP server uses the standard port). You should take this issue up with Cox.

what file do is used for sendmail configuartion? I looked in the zenphoto_sendmail.php, but I don't see any port settings or much anything else.

You need to ask that your host, that is done on the server.

I understand about that my host will is in charged of the blocking the port 25, but I have a mail redirect setup with a dynamic dns provider and I should be able to use it like I do for my exchange mail server. I just need to know what file holds the settings for the sendmail and then I should be able to adjust it.

Both sendmail and phpmailer are plugins and therefore found in zp-core/zp-extensions.