Open Studio error

Hello,

I have installed Rhino, Grasshopper (with Ladybug and Honeybee) by following the instructions of this link : 

https://github.com/mostaphaRoudsari/ladybug/blob/master/resources/I...

But the thing is that Open Studio seems to not be working, on the Honeybee_Honeybee I got the issue : 

Honeybee cannot find OpenStudio on your system.
You wont be able to use the Export to OpenStudio component.
Download the latest OpenStudio for Windows from:

https://www.openstudio.net/downloads

I have installed Open Studio v2.1 at C:\openstudio-2.1.0.

Do you have any idea why Open Studio is not considered as installed by Honeybee ?

Thank you for your time