[SOLVED] AutoAction "Register a new user" and blank page after update user profile edit.

AutoAction creating a new user causes an error and a blank page if called when user edit his profile (the user is created, but the page gets a blank page error when saving). At the same time, the same AutoAction called from the front of the profile using "CB Core Fields Ajax" works without any problems. So maybe the problem is not so much with creating the user, but with refreshing the page after pressing "Update" and saving profile with this AutoAction?

Also tested today (2021.07.29) on your demo.cbdemosites.com site as a Demo User. I have created a text field on your Demo site and an autoaction run onAfterUserUpdate on [var1 ...] not Equal to [var3 ...] and Equal to ... - same effect, blank page if user saves from profile editing and ok if he uses the Ajax front.
I use it and it worked fine during testing a few weeks ago, I can't tell when it stopped working, I restored a backup from a few days ago and the same problem, so sometime before.

Enable debug mode and maximum error reporting in Joomla global configuration next in your auto action under Parameters enable Debug. Now retry and see if any errors output. Not every auto action type is suitable for every location.

Damn sorry! i could have done this before... error output:

CBPaid Debug Message
USER ERROR: cbpaid:onAfterUserRegistration: No free plan but no plan chosen ! in \xampp\htdocs\...\components\com_comprofiler\plugin\user\plug_cbpaidsubscriptions\cbpaidsubscriptions.php on line 616
Trace:called in class cbpaidErrorHandler::_error_handler_callable(256, "cbpaid:onAfterUserRegistration: No free plan but no plan chosen !", "\xampp\htdocs\...\components\com_comprofiler\plugin\user\plug_cbpaidsubscriptions\cbpaidsubscriptions.php", 616, array("user" => object(CB\Database\Table\UserTable), "rowExtras" => object(CB\Database\Table\UserTable), "bool" => true, "_PLUGINS" => object(cbPluginHandler), "params" => object(cbpaidParamsConfig), "registrationPlansEnabled" => "1", "enableFreeRegisteredUser" => "0" (...)

It turns out to be a conflict with CBSubs settings: Allow Free Registered Users (without subscriptions) is set to No...
Yep... after setting Allow ... to Yes, the problem with creating a user with auto-action disappears.

After auto creating a user, I assign a Plan to him in the next step another AutoAction, but maybe I could use Fields settings when creating in 1st step, and keep Allow... to No?

You're trying to create a user without a subscription, but your site requires one. There isn't really a workaround for that except adjust "Allow Free Registered Users (without subscriptions)" as you've already found. CB Auto Actions isn't able to send a plan selection with its registration action.

Thanks for the clarification. This is unfortunately painfully logical