The confirmation email should read this at the bottom:
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Where to go from here?
If you are new to Akeeba Subscriptions, we suggest that you take a look at our User's Guide.
When you feel comfortable with the instructions, download Akeeba Subscriptions Professional. From that page, please click on the latest release (always on the top of the page). If you have an older version of Joomla! and/or PHP please consult our Compatibility page to find the correct version for your site, go back to the download page, find that release and click on it. Either way, you will see several items on the new page. You will have to download the one that reads "Akeeba Subscriptions Professional" by clicking on its title. Install Akeeba Subscriptions Professional using Joomla!'s extensions installer. More detailed instructions can be found in the first few pages of our User's Guide.
If you run into any problems, do not hesitate to post a support request in our support ticket system. We're here to help!
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Obviously there are links to the user's guide, download page and compatibility page.
The requirement to log out and back in is a limitation in Joomla! itself. You will have the same issue on your site using Akeeba Subscriptions or any other subscriptions component. Joomla! caches the access rights of users in the user session. In short, this means that you need to log out and back in for Joomla! to "see" the new user group assignment of your user.
I am working on a workaround which will be published in the next version of Akeeba Subscriptions. When a subscriber gets back to the "Thank you" page on the site he is transparently logged out and back in. The only obvious problem is that if the subscriber does not get back to that page (as happens, unfortunately, with 2Checkout) there is no way this workaround can work. I consider this a broken behaviour of Joomla! which has to do with the architecture of the ACL system. The ACL system is powerful but extremely slow. In order to work around the bad performance they are forced to cache the access privileges in the user session. The result is that when you change the user group assignments of a user they are not taken into account until the next time he logs out and back in.
Now you have the executive summary of the full picture of Joomla! ACL issues. I hope this information will be useful to you.
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
Please keep in mind my timezone and cultural differences when reading my replies. Thank you!