Hi,
this is a nagios plugin. So don’t use the Checkmk plugin directory. You can save the files e.g. into c:\program files…\check_mk\check_iis. Then add to your check_mk.ini file:
[mrpe]
check = IIS_AppPools c:\program files...\check_mk\check_iis\check_iis.exe --inventory-pools
Karl