Can't ping host ESX ip's

I can't think of anymore things to try.

i've gotten as far as installing ESX but can't add the host in VI.

Can't ping the IP's (i have 3 boxes setup) .. and can't ping anywhere from the ESX box out.

On these blades previous were win2k3 with the same IP's and everything was good. So we can rule out switch config/ip conflicts

I've restarted networking,disabled firewall on ESX, and checked the IP's which are OK. Any suggestions???