Cannot replicate.

My user saved fine.

Are you sure you provided a valid email address, username and name?

Please DON'T do testing on https://demo.joomla.org/ Its a customised version of Joomla provided by SiteGround.

Get the same issue when i create a user in demojoomla.com

Like I said - DONT test on the Joomla demo domains- that is a CUSTOMISED VERSION of Joomla provided by SiteGround

Please test on KNOWN entities - like your own websites on a normal webhost, or locally in a development evnvironment.

Can't replicate here either, creating a new user assigned to the "Publisher" group works fine on 3.7.1.

I tried not providing a valid email address, username or name gives a warning to say so rather than the error reported.

Are you sure you have all the steps listed accurately? It works fine for me with the ones you have listed, but they're not complete as they don't include setting the above fields as @PhilETaylor points out.

Set to "closed" on behalf of @franz-wohlkoenig by The JTracker Application at issues.joomla.org/joomla-cms/16093

closed as no Core Issue.

I can reproduce the issue on webhost https://www.mittwald.de ,
valid email and other fields.

System info:

PHP Built On Linux s1112 2.6.32.71-kvm-32cpu-06 #1 SMP Fri Dec 2 15:35:31 CET 2016 x86_64
Database Version 5.7.17-11
Database Collation utf8_general_ci
Database Connection Collation utf8mb4_general_ci
PHP Version 7.1.1
Web Server Apache
WebServer to PHP Interface fpm-fcgi
Joomla! Version Joomla! 3.7.1 Stable [ Amani ] 17-May-2017 14:00 GMT
Joomla! Platform Version Joomla Platform 13.1.0 Stable [ Curiosity ] 24-Apr-2013 00:00 GMT
User Agent Mozilla/5.0 (Windows NT 10.0; WOW64; rv:53.0) Gecko/20100101 Firefox/53.0

Set to "open" on behalf of @franz-wohlkoenig by The JTracker Application at issues.joomla.org/joomla-cms/16093

reopened.

Can't confirm Issue.

System information

3.7.1
macOS Sierra, 10.12.4
Firefox 53 (64-bit)

MAMP 4.1.1

• PHP 7.0.15 and 7.1.1
• MySQLi 5.6.35

Can't reproduce issue on host https://www.schwarzkuenstler.com

PHP Built On Linux srv16.schwarzkuenstler.info 2.6.32-042stab120.19 #1 SMP Mon Feb 20 20:05:53 MSK 2017 x86_64
Database Version 5.6.35
Database Collation utf8_general_ci
Database Connection Collation utf8mb4_general_ci
PHP Version 7.0.19
Web Server Apache
WebServer to PHP Interface cgi-fcgi
Joomla! Version Joomla! 3.7.1 Stable [ Amani ] 17-May-2017 14:00 GMT
Joomla! Platform Version Joomla Platform 13.1.0 Stable [ Curiosity ] 24-Apr-2013 00:00 GMT
User Agent Mozilla/5.0 (Windows NT 10.0; WOW64; rv:53.0) Gecko/20100101 Firefox/53.0

I tryed "Reinstall Joomla core files" on host mittwald, issue is still there,
anything else I can test?

When I want to create a new user on 3.7.1, I get:
ERR_CONTENT_DECODING_FAILED

using
PHP-Version 7.0.11
Webserver Apache
PHP-Interface für den Webserver fpm-fcgi
Joomla!-Version Joomla! 3.7.1 Stable [ Amani ] 17-May-2017 14:00 GMT
Joomla!-Plattform-Version Joomla Platform 13.1.0 Stable [ Curiosity ] 24-Apr-2013 00:00 GMT
Browsererkennung Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.36

ERR_CONTENT_DECODING_FAILED

That is nothing to do with creating a user at all.

This is because you have GZIP enabled in Joomla Global Config, but your server is also encoding the output.

Disabled GZIP in Joomla Global Configuration as you dont need it on your server which is already encoding the output.

OK I did that and user registration works.

But why does this happen only now (didn't happen before) and only there (other editing fields worked correctly?

I found the reason for this issue at mittwald (https://issues.joomla.org/tracker/joomla-cms/11131):
Empty field "From Email" in global configuration - Server - Mail Settings.

Well that would have been obvious to me that this needs setting to send email...

Thank you for support and sorry for wasting your time, it is not my site, I always fill in an email on installation, a clearer error message would be nice...

I can now replicate this by removing the From Address in Joomla Global Config.

Call to a member function addRecipient() on boolean

You do realize turning on debug mode will give a stack trace to the error, right?

You do realize turning on debug mode will give a stack trace to the error, right?

I do yes, I doubt the others above are developers :)

PR to test #16107

Set to "closed" on behalf of @franz-wohlkoenig by The JTracker Application at issues.joomla.org/joomla-cms/16093

closed as having PR #16107

Im starting to think @franz-wohlkoenig is a robot.. he is far too fast to be a human...