500 server error after install

Just after installing and enabling, I get the classic 500 server error on /wp-admin. Happened a few times in the last weeks, different servers – just after WP core update. Can’t make it work. Anyone else experiencing the same problem? There’s just one plugin, this one. Classic WP and theme, no other plugins.
Might be something to do with some server configuration, cheap providers, but it didn’t happen before the core update.

• This topic was modified 6 years, 6 months ago by catalinfx.