Windows remote "net rpc shutdown" gives me WERR_CALL_NOT_IMPLEMENTED error

I'm trying to remote shutdown my HP Microserver N40L running Windows Home Server 2011 with a shell script on my Synology Ds413j.

At the end of my backup script, it runs to shutdown the HP machine:

Code:

net rpc -I 192.168.5.4 -U Administrator%******** shutdown -s -t 0 -f

But this line at the end and nothing happens on the HP machine:
result was: WERR_CALL_NOT_IMPLEMENTED

I've checked both "fixes" mentioned here: http://potassium.1338.at/index.php?id=1269
Using Administrator, it belongs to Administrators group, so does have remote shutdown privilege. The registry key is already present and set to 1.

Is there something else I've missed?

Alternatively, how would you remote shutdown a Windows machine using a shell script?



EDIT:

I've found the problem!

I run a simple BAT script on Windows start-up to time shutdown in a few hours, because I sometimes remote desktop in and often forget to it down. Also due to not being able to carry out remote shutdown from NAS.

This WERR_CALL_NOT_IMPLEMENTED will no longer appear if I remove the timed shutdown command. (eg, don't do "shutdown -s -t 10800") The error will appear when there is already a timed shutdown in place.

So now I set schedules to shutdown on particular hour of the day.

 

Is WinRM enabled on the server?

 

Thanks for your response. I just checked,

Code:

C:\Users\Administrator>winrm quickconfig
WinRM already is set up to receive requests on this machine.
WinRM is not set up to allow remote access to this machine for management.
The following changes must be made:

Create a WinRM listener on HTTP://* to accept WS-Man requests to any IP on this
machine.
Enable the WinRM firewall exception.

Make these changes [y/n]? y

WinRM has been updated for remote management.

Created a WinRM listener on HTTP://* to accept WS-Man requests to any IP on this
 machine.
WinRM firewall exception enabled.

C:\Users\Administrator>winrm quickconfig
WinRM already is set up to receive requests on this machine.
WinRM already is set up for remote management on this machine.

After that, still same error.

 

Firewall setup correctly? Network set for discovery and sharing?

 

Any particular services need to be enabled for the firewall? It's all default. I've tried with firewall turned off, same error.

Yes and yes.