Try shelling the windows shutdown process.
Example:
'--------------------------------------
' Shelling shutdown process
Shell("shutdown.exe -s")
'--------------------------------------
Usage:
shutdown [-i | -l | -s | -r | -a] [-f] [-m \\computername] [-t xx] [-c
"comment"]
[-d up:xx:yy]
-i Display GUI interface, must be the first
option
-l Log off (cannot be used with -m option)
-s Shutdown the computer
-r Shutdown and restart the computer
-a Abort a system shutdown
-m \\computername Remote computer to shutdown/restart/abort
-t xx Set timeout for shutdown to xx seconds
-c "comment" Shutdown comment (maximum of 127 characters)
-f Forces running applications to close without
warning
-d [p]:xx:yy The reason code for the shutdown
u is the user code
p is a planned shutdown code
xx is the major reason code (positive
integer less than 256)
yy is the minor reason code (positive
integer less than 65536)