Do you have any idea where this error is coming from? After installation and activation of paid Artio SEF, only if a user is logged in, after clicking on any read more or any articles, this error will show up: 500 Server Error

Otherwise the link is okey and it is working without any problem as soon as user is logged out.

Thanks
Toby

Hello,
not quite sure, this is not an usual problem.
I would try to check what other plugins you have installed or whether there is any customization in your Joomla.
Also, proper ordering of the plugins should be checked. Make sure the JoomSEF plugin is ordered first. (on the other hand, if you use cache plugin, that should be ordered among last ones) (in system plugins group)

Thanks for replay, probably this was as you suggested. After I changed ordering of plugins, now it works.