forge 1.11.2 wont load

Put the summary of the bug you're having here

i was expecting when i ran minecraft with the forge 1.11.2 version, it would run minecraft forge 1.11.2

what actualy happened was i got an error message saying "launche failed. the version you are trying to play inherits properties from an unknown version

Steps to Reproduce:
1.open the launcher
2. click forge 1.11.2 in the version list
3.click play