Your error is telling me the ads are getting marked sold if your running the cron task. You need to be running that to expire. The email error your referring to is showing me you are running the cron. The error is because as I have stated your admin email in the program must be set to whatever email your admin user in vbulletin is set to. If that happens your error disappears.
Our classifieds system if your using messaging yes you need to set the email to match that of the admin user because thats how private messaging thing. A private message is sent from a userid to a userid. I wrote a little function to grab the userid but since that varies by site userid wise you have to grab the userid by something so we use email. It is a messaging thing. You do not have to set your admin email to your forum admin email if you do not use messaging only if you do.
Ads are expired using the cron as follows any ads older than when the script is ran are expired.
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