Task notification Mail

Dharsana, In old versions it can be done through designer under alerts tab but now it is not available in designers tab. Now it can be only done through smart service. We faced a similar issue in past and found that these alerts are disabled explicitly by designers who designed other applications which are running in same environment for all users to avoid emails for task assignment.
@Does it mean it will send mail only if the user accept the task?
It goes to all users to whom it is assigned to

Raviteja Varma Jampana Please ignore the above comment and it is working as I expected.

Raviteja Varma Jampana Please ignore the above comment and it is working as I expected.

From 16.3 version you can control the task notification emails. Look for User Input Task properties.