Issue Can't access the plesk installer from webinterface

[affeldt]

Hello,

First, I’m new to all of this, so please forgive me if I’m being stupid

I have a Plesk install running on a CentOS 7 and I can' access the web interface of the installer e.g. my-domain.de:8447
I also tried to put in the ip-address but also no success. The "normal" web interface running on port 8443 is working fine. Also the plesk installer from the command line is no problem. I also tried to use other browsers cuz Firefox is giving me error "secure connection failed: PR_END_OF_FILE_ERROR" but chrome also let me down with an "ERR_CONNECTION_CLOSED"
The plesk Firewall says the plesk installer Rule is activated and the output of this command (iptables -nL | grep 8447) also seems ok for me
ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:8447 ctstate NEW,UNTRACKED
I searched in the forum but at least I found nothing similar. I hope anyone of you know what this could be. If I can help you with any log files please let me know what and where I can find it.

Thank you in advance.

 

[IgorG]

Looks like service installer is not started.
Try to navigate Tools & Settings > Updates

 

[affeldt]

Looks like service installer is not started.

How can i check if the service is running?

Try to navigate Tools & Settings > Updates

When I do this, the page (https://myhost.mydomain.de:8447/?secret=xxxxxxxx&locale=de-DE) opens with the same error