VOID VDDDeInstalllOHook(hVdd, cPortRange, pPortRange)
IN HANDLE  hVdd;
IN WORD  cPortRange;
IN PVDD_IO_PORTRANGE  pPortRange;
VDDDeinstalllOHook unhooks the I/O ports previously hooked by a VDD.
When VDDDeinstalllOHook cancels a hook, the default hook on those ports subsequently returns 0xFF when reading the port and ignores write operations.
VDDInstalllOHook