I have tried uninstalling it and have searched other answers. None of them have worked; IDLE opens, but I can't run anything I write.
In Windows 10
1. Type in "Controlled folder Access"
2. Select "Allow an app through Controlled folder access" Select yes to "UAC"
3. Click on "+ Add an allowed app"
4. Select "recently blocked apps"
5. Find the executable for the C:\Python27
6. Click the + to add it.
7. Select Close
Then try running the Python Shell again. This worked for me 100%
Also, add exception through Windows Firewall Python27 select Private and Public.
IDLE's subprocess didn't make a connection. Either IDLE can't start or personal firewall software is blocking connection