Website offine again

Hello,
during this past three days my website ( http://sgcs.altervista.org ) has been offline due to unknown issues. I already told that I didnt and I keep not touching website's files so this has nothing to do with that. I already posted an thread here and I was told the someone was investigating this issue.
This keeps happening and if I am correct this started almost one month ago. I keep receiving error messages as the message present below:

Error 500

An error occurred.

This error may be due to an erroneus .htaccess file, added by you or by a script in the current directory, or by an external connection to an unreachable remote host

To check the .htaccess file you should login in your control panel, click on file management and then on the gear icon.

Go back

I would like, once again, to request another investigation on this issue as I need the website to be online as soon as possible. Once again thank you for your time.

[karl94]

We are gathering all the relevant information about this issue. Please don't open new threads, instead continue to post in the other one.