Not able to configure cRIO-9036 to DHCP only mode programmatically

[Nammiraj]

I have cRIO 9036, I am trying to set it to "DHCP only" mode

 From NI MAX

1. I am able to configure Ethernet Adapter eth0 to "DHCP only" from MAX. 
2. Save
3. Restart
4. NI Max cannot find the cRIo until cRIO obtains IP address from a DHCP server. - This is fine

Now Programmatically (attached Code)

using nisysconfig.lvlib and property node, when trying to set the cRIO in "DHCP only" mode.

I get error -2147024809.

LabVIEW: (Hex 0x80070057) One or more arguments are invalid.
=========================
NI System Configuration: Invalid parameter.

If it can be done from NI MAX, then it should be possible programmatically. What am I missing? Please find the attached code. 

Please help.

Thanks,

Narmada