Following is the fix if you get the ” 500 internal server error ” when accessing hsphere control panel,

1) Restart the control panel executing the following commands on the control panel server,

$ /etc/rc.d/init.d/httpdcp stop
$ sleep 10
$ /etc/rc.d/init.d/httpdcp start

Normally after restarting the CP the error is fixed , but even after
restarting the control panel the error is not fixed then possibly your
PostgreSQL database is down.

you can start the postgreSql using the following command,

$ /etc/init.d/rc.d/postgresql restart
restart control panel after this and the ” 500 internal server error ” will
vanish.