After a clean new install of ISPConfig 3.1 got 403 Errors As the title says! I did a new and clean install of Debian 8.7.x and ISPConfig 3.1 from 'Ground Zero'! This time I didn;t used HTTPS, just HTTP for ISPConfig. I also added Softaculous Script Installer to it and that works. I've no problems to open the ISPConfig from local IP 192.168.1.18, public IP and Web-Domain using the port 8899 which I assigned for ISPC. I use Debian 8.7.x because I was getting a lot of problems with Debian 9 and PHP 7, I need PHP5 at least! Now, I was trying to install some scripts from Softaculous like FormTools, Soholaunch and OwnCloud. the first do installed fully, but couldn't be started, while OwnCloud aborted the install at 88% giving the error: and for FormTools and Soholaunch the error is: I checked all settings in ISPC and didn't found any problems, and all settings for Websites etc. should be correct (I think!). The only thing which makes me think a bit is the Google DNS Servers which are used in ISPC. Maybe I should change them to my Registrars Nameservers? Or what else could be the problem? Thanks for any advice.