How to wirte command to update the ImagePath REG_EXPAND_SZ type key ?

Hi

I am trying to edit an existing registry key from a .reg file. I want to change the vaue of the path below command is not updating registry key

How to wirte command to update the ImagePath ?

Windows Registry Editor Version 5.00

[HKEY_Local_Machine\System\CurrentControlSet\Services\c2wts] "ImagePath"=REG_EXPAND_SZ:"%ProgramFiles%\Windows Identity Foundation\V3.5\c2wtshost.exe"