OK, here is my setup:
I am setting up registration for a convention. There are no users of this Joomla installation except for the site administrators.
I have it set up for group or individual sign up, using Paypal standard. IPN is turned On, Autoreturn is turned off. No matter which I pick (group or individual), I go through the form, get sent to the paypal site and I get charged for the event. However, when I go to records, there are no registrants listed
First, make sure you have the latest package. Version (as of today) is 2.7.4b. That's the first thing to check. With the latest version, if you still have this issue, it will definitely be IPN related. Besides what you've mentioned, check site permissions. Make sure all directories (starting from the top level joomla directories) are 755 and files are 644. Also make sure you have no firewall blocking IPN from hitting your server. If you can't sort it out, submit a ticket... but there is not a bug that would cause this. Thanks.
I'll look at the above suggestions, but in the meantime, you are apparently avoiding the real issue - you have a distinct error in logic. There have been other threads on this that you have not addressed and the above answer is another dodge. The problem is not the IPN not hitting the site, it's the records not being created! I firmly believe the records should be created first in DT Register's database and THEN updated with the IPN if there is a successful payment generation.
Then, if there is a IPN problem, we don't wind up with angry guests who have been charged for the convention but don't have the perks of pre-registration available to them because we have no records in the event of them ever registering.
I notice you have not addressed those threads - would you provide an answer as to why this is not done? This is really a dealbreaker if you refuse to change this behavior and I will have to request a refund.