[fcgid:warn] Error while trying to install CMS

Hello,
I'm trying to install WHMCS on fresh Debian 8 ISPCONFIG installation. I've tried PHP-FPM, FAST-CGI active desactive suExec and other things to don't have 500 error while installer is creating database (I think). In the error.log I got these 2 errors :

Code:

[Thu Oct 22 11:32:24.400045 2015] [fcgid:warn] [pid 17959] (104)Connection reset by peer: [client xxx.xxx.xxx.xxx:42806] mod_fcgid: error reading data from FastCGI server, referer: http://xxx.com/clients/install/install.php?step=4
[Thu Oct 22 11:32:24.400182 2015] [core:error] [pid 17959] [client xxx.xxx.xxx.xxx:42806] End of script output before headers: install.php, referer: http://xxx.com/clients/install/install.php?step=4

Does anyone have an idea how I can resolve this error ?

Thank's a lot

 

Thank you,
I've resolve my error with your help. Now I've a problem with API :
SOAP Error: Could not connect to host (When HTTPS enabled)
SOAP Error: Bad Request (When HTTPS disabled)

 

Okay I've resolved the error by adding this :
'stream_context'=> stream_context_create(array('ssl'=> array('verify_peer'=>false,'verify_peer_name'=>false)))

Now when I ask ISPConfig api to add client, domain service ect ... I get this from ISPconfig API : "Internal Server Error" and in error.log :

Code:

[Fri Oct 23 17:20:56.546568 2015] [fcgid:warn] [pid 30671] (104)Connection reset by peer: [client 2001:41d0:8:xxxx::1:48878] mod_fcgid: error reading data from FastCGI server
[Fri Oct 23 17:20:56.546744 2015] [core:error] [pid 30671] [client 2001:41d0:8:xxxx::1:48878] End of script output before headers: index.php

 

seems, that you ssl-cert could not be verified. you can try to add the intermediate-certs as bundle.

 

I've found an other solution which is to add this "'stream_context'=> stream_context_create(array('ssl'=> array('verify_peer'=>false,'verify_peer_name'=>false)))".

Now I've this problem :

 

How I can get more details about this error ?