Hmm, have you tried to resetting the system configuration (http://pubs.vmware.com/vsphere-50/index.jsp?topic=%2Fcom.vmware.vsphere.install.doc_50%2FGUID-AD450D...)? If you do not want to take such a harsh step you can log into the shell and try some esxcg- or esxcli commands to see what is going on...
esxcfg-vswitch -l
esxcfg-vmknic -l
esxcfg-route
Hope this helps! === If you find this information useful, please award points for "correct" or "helpful". ===
