I can't get CWP started up after rebooting the VPS

I can't get CWP started up after rebooting the vps. I don't have access to SSH, i get session closed. It has been working fine for couple months.

I installed antivirus & anti-spam, which may be stressing the resources on my web server. It started working after an hour i disabled the antivirus and all, and than 20 min later it's not more accessible.

Do you have a snapshot your can restore to?
That sounds like your best bet.

Did you install/activate ClamAV and anti-spam via CWP?