I want to run the simple activity" messege box" but while press run tab it show an error like "could not start exucator.The system can not find specified file"

[Vaibhav_Savaratkar]

I want to run the simple activity" message box" but while press run tab it show an error like “could not start executor. The system can not find specified file”
please help me . I am beginner if any changes I have to make in setup then inform me.

[postwick (Paul)]

Click “Copy to Clipboard” or expand Details, and paste the entire text of the error here.