I have tried to "check update" in android studio
Help>Check for Updates
but it says
Connection failed. Please check your network connection and try again
But my Internet is working fine. .I've also tried to switch off my firewall. Is this bug of google service?
Update : Whenever updates | installations are failed, start the android studio as administrator.
Old Answer: This is possibly a bug of Android Studio.
The following steps may help to fix this issue:
Open configuration
Select Settings
Select HTTP Proxy
Set to use no proxy
Restart Andriod studio