Hi,
try to clean your browser cache.

Hi,
this not seems direct connected to Easy Profile, this seems that you have some corrupt data in Database.

Try to recreate Users List menu item. If also this not works you need to check you php error to understand where does the error.

Also, can you please post me your site link to see the error?

The error is on both type of list´s.
user list
or
user list table

Hi,
each webserver have a PHP error log. You probably can find it via FTP or from hosting cpanel.

Anyway this seems a Joomla issue, I hope Joomla Dev Team can fix this ASAP.

For now you can try following solution:
- go to /libraries/vendor/joomla/registry/src/Format and edit Json.php:
- Comment the line 72:

throw new \RuntimeException(sprintf('Error decoding JSON data: %s', json_last_error_msg()));

This temporary solution come from https://github.com/joomla/joomla-cms/issues/12460

Otherwise please post me your site details, we will investigate about this. You can use the form below the reply in "Site Details" tab.

a small question:
Joomla User Management Backend works?

Because of your question, yes there is no problem on my backend, it workes fine

Also if you try to edit old user profiles?

There is no problem before, with 3.6.2 joomla.

In a very old Joomla sites (probably upgraded from 1.5), some parameter for users (and modules) are written with a not valid format. Joomla 3.6.3 launch an exception when found this error. In version 3.6.2 and earlier this error comes simply ignored.

This site was createt with joomla 3.4.1
I hope there is ASAP a sollution, otherwise i will install 3.6.2 back.
Or is there an other solution?

Or is there an other solution?

The solution is to find where there is not valid JSON in db and fix it
But this is not simple and require PHP and Joomla Dev knowledge.

We provide this type of support only to paid members because this require much time.