I've switched from wordpress hosting to website hosting and I've installed Wordpress. It's gone more than 1 year since I've adopted this hosting solution for wordpress and something is changed 'cause the process was a little bit different and more simple.
I've uploaded via FTP a new theme, updated the theme list in MyCMS and activated the new theme. Unfortunately when I try to login the new theme, it's impossible due this error:
Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.
Please contact the server administrator to inform of the time the error occurred and of anything you might have done that may have caused the error.
More information about this error may be available in the server error log.
This happen with every new theme I upload via FTP and then install in MyCMS.
If in MyCMS I activate a default theme, I can log in the same one in the classic WP UI and in appearance I can see the theme I've uploaded but again, even if I try to activate theme from here, the same error appears.