Hi,
all registry keys have an default value. The default value cannot be set by its name “(Default)”, it must be set with specific option of reg.exe.
To set the default value use the reg.exe /ve switch. For example: This resets the default action for the .cmd file extension.
D:\> reg add HKEY_LOCAL_MACHINE\SOFTWARE\Classes\cmdfile\shell /ve /d "" /f
Michael
Thanks! This catches me out every time as it can be 3/4 years before I need to change the (default) aka /ve value.