Nagios not running on Ubuntu

I have installed Nagios 3.0.3 on a Compaq 6710b laptop running Ubuntu 8.04 following the instructions for installation… On the web browser the error is read as “Could not read object configuration data"
On the command line , for the command " nagios -v /usr/local/nagios/etc/nagios.cfg”, all the config files were verified and the displayed result was " Things look okay - No serious problems were detected during the pre-flight check"

But for the command " tail -f /usr/local/nagios/var/nagios.log" , the display shown was “[1220174429] Error: Cannot open main configuration file ‘/root/main_config_file’ for reading!”.

The installation is under /usr/local/nagios and all the configuration files are under the /etc folder inside the nagios folder.

Please help me fix the problem. Thanking you in advance.
vadivel

Hi,

I’m not sure, but could you have a look at your cgi.cfg file ? maybe you’ll spot something wrong