Asio utility

Most likely that was a cmd file to change the driver mode in the registry.
 
First, confirm the registry path where the value to be changed is located:
Open a cmd prompt (admin).  Right click start button and choose cmd prompt (admin)
Then, you can use the query cmd like so:
 
reg query "HKCU\Software\Cakewalk Music Software" /f Core /s
 
You should see it list the location of the found value.
 
HKEY_CURRENT_USER\Software\Cakewalk Music Software\SONAR\Platinum
Core REG_DWORD 0x20
 
For SONAR 5 it may list something like:
 
HKEY_CURRENT_USER\Software\Cakewalk Music Software\SONAR\5.0
Core REG_DWORD 0x29a
 
Second, something like this should update it to ASIO:
reg add "HKCU\Software\Cakewalk Music Software\SONAR\5.0" /t REG_DWORD /v Core /d 0x29a /f