Seems like someone removed root's access on the VIC, you're going to need to go into the VIC with a user with Administrator permissions. The click on your host, go to the Permissions tab and change root back to administrator.
I half remember that there is a way to do this on the console, but I'm having trouble finding it right now.
EDIT: Found the console stuff
Ok, yep you can fix this on the console.
You'll need to edit the file
/etc/vmware/hostd/authorization.xml from the console.
You should seen something like this:
<... SNIP Other USERS ... >
<... SNIP Possible custom roles ...>
The piece you are going to want to change is the "ACEDataRoleId" (-1 is Administrators)
you might have to restart the hostd service with
service mgmt-vmware restart after your changes.