"Unreachable: Hard" issue


i am hoping someone can help me out, i am somewhat new to Nagios but i did manage to get it working on 3 seperate servers.
The problem i have now is this: ALL my devices i have in the host file seem to not be reachable by nagios, (all i am doing is a PING command), for some reason the response i get is either “DOWN;HARD” or “UNREACHABLE;HARD”.
Now, if I do a manual ping using the “Submit passive check…” option then it seems to work until the next time Nagios has to do it by itself & then I am back to the above issue.
Looking at the log file for nagios here is what I get:
"[1130223600] CURRENT HOST STATE: [www.yahoo.com;UNREACHABLE;HARD;1;(No](http://www.yahoo.com;UNREACHABLE;HARD;1;(No) output!)“
”[1130223600] CURRENT SERVICE STATE: [www.yahoo.com;PING;CRITICAL;HARD;1;(Return](http://www.yahoo.com;PING;CRITICAL;HARD;1;(Return) code of 127 is out of bounds - plugin may be missing)"

I do have all the plugins in the correct directory, i already checked that.

Any help would be appreciated.

Thank you


has the check_ping plugin the correct permissions?
Try logging on as the nagios user and try running thje plugin from command line.