I was using G-WAN v7.12.2, everything is OK. But when I changed to G-WAN v7.12.6, it started without error but I can't visit my site. When I use Linux command
"sudo netstat -tnlp"
to check, there was no G-WAN listening to any port.
I changed back to v7.12.2. Everything came back, OK.
I put G-WAN into /home/www-data. All files and directories are of www-data user and group.
I just downloaded G-WAN 7.12.6 64-bit and started it both as the current user and as root without any issue.
You probably have a script compilation issue that prevents G-WAN from starting. Check the G-WAN log files or start G-WAN in the interactive mode to see terminal feedback.
Another possibility is that you have a crash (maybe due to out-of-sync. G-WAN headers). Always make sure that you copy the latest G-WAN headers and libraries on your old installation when you upgrade.
Here again, G-WAN log files should tell you what happened.