Web GUI does not work after upgrade to 2.7

Question

Hi there,

I followed this tutorial for the upgrade  http://wiki.ocsinventory-ng.org/03.Basic-documentation/Updating-the-server/ but now i got a white page. 

The logs at /vars/logs/apache2/error.log are:

[Fri May 22 08:37:00.364188 2020] [mpm_prefork:notice] [pid 5436] AH00163: Apache/2.4.25 (Debian) mod_perl/2.0.10 Perl/v5.24.1 configured -- resuming normal operations

[Fri May 22 08:37:00.364247 2020] [core:notice] [pid 5436] AH00094: Command line: '/usr/sbin/apache2'

[Fri May 22 08:37:39.306044 2020] [:error] [pid 5442] [client 192.168.1.234:21816] PHP Warning:  mysqli_real_connect() expects parameter 6 to be integer, string given $

[Fri May 22 08:37:39.375698 2020] [:error] [pid 5442] [client 192.168.1.234:21816] PHP Warning:  mysqli_real_connect() expects parameter 6 to be integer, string given $

[Fri May 22 08:37:39.375724 2020] [:error] [pid 5442] [client 192.168.1.234:21816] PHP Warning:  mysqli_select_db() expects parameter 1 to be mysqli, null given in /us$

[Fri May 22 08:37:39.375738 2020] [:error] [pid 5442] [client 192.168.1.234:21816] PHP Warning:  mysqli_query() expects parameter 1 to be mysqli, null given in /usr/sh$

[Fri May 22 08:37:39.375747 2020] [:error] [pid 5442] [client 192.168.1.234:21816] PHP Warning:  mysqli_fetch_object() expects parameter 1 to be mysqli_result, null gi$

[Fri May 22 08:37:39.376058 2020] [:error] [pid 5442] [client 192.168.1.234:21816] PHP Warning:  mysqli_real_connect() expects parameter 6 to be integer, string given $

[Fri May 22 08:37:39.376072 2020] [:error] [pid 5442] [client 192.168.1.234:21816] PHP Warning:  mysqli_select_db() expects parameter 1 to be mysqli, null given in /us$

[Fri May 22 08:37:39.376079 2020] [:error] [pid 5442] [client 192.168.1.234:21816] PHP Warning:  mysqli_query() expects parameter 1 to be mysqli, null given in /usr/sh$

[Fri May 22 08:37:39.376085 2020] [:error] [pid 5442] [client 192.168.1.234:21816] PHP Warning:  mysqli_fetch_object() expects parameter 1 to be mysqli_result, null gi$

[Fri May 22 08:37:39.376091 2020] [:error] [pid 5442] [client 192.168.1.234:21816] PHP Warning:  mysqli_query() expects parameter 1 to be mysqli, null given in /usr/sh$

[Fri May 22 08:37:39.376096 2020] [:error] [pid 5442] [client 192.168.1.234:21816] PHP Warning:  mysqli_error() expects parameter 1 to be mysqli, null given in /usr/sh$

It does not seems something really bad but i don't know how to fix this.

i would greatly appreciate it if you kindly give me some feedback :)