How to automatically send an SMS if a call is missed? Due to a busy schedule, missed call are a constant, and many times the person calling insists on keep calling until I answer.

The ideia is to automatically send an SMS with a pre-defined message to let the caller know that I'm on the phone or otherwise busy, and that I will be returning the call as soon as possible.

So, how can I send an automatic SMS for missed calls?
Here is a workaround using Tasker:

Profile (or Trigger)

Create a Profile which allows sending to contact with the missed call:


Goto Profiles Tab and click the "+"
Event >> Phone >> Missed Call
Tap back to exit from this window


Task

You will notice as soon exit, you will be prompted to link this to a Task


Scroll all the way up the Task list select "New Task + "
You can name this Task SendSMSmc or anything.
Click "+" to add new Action
Phone >> Send SMS [Number:%CNUM Message ( e.g I am currently busy at the moment, I'll call later)
Tap back to exit from this task
Press back all the way to exit (Your task is saved)


Explanation: When a call is received, and even  if you are not able to answer it, 
the "Missed Call trigger" allows Tasker to send a message containing the body test:
"I am currently busy at the moment, I'll call later" to the missed call number" where %CNUM is the missed call number.

Hope this helps other users well