Here are all the list of reasons for filing TDR of ticket for refund. If it is e-ticket you can simply file it online on the next day of journey day and up to maximum of 30 days. Otherwise you forfeit your right for refunds admissible.

In case of paper (PRS) tickets you may need to take authorization from station master or TTE for partial travels, not travelled etc otheriwse your claim will be held up without any response from Railways.

1. AC Failure.
2. After Charting No Room Provided.
3. Change In Reservation Status From Confirmed To Wait listed/Part Wait listed/RAC After Chart Preparation.
4. Difference Of Fare As Passenger Traveled In Lower Class.
5. Difference Of Fare In Case proper Coach Not Attached.
6. Party Could Not Cancel Because Chart Prepared At Originating Or Previous Remote Location.
7. Party Partially Confirmed/Wait listed And All Passengers Did Not Travel.
8. Party Partially Confirmed/Wait listed And Wait listed Passengers Did Not Travel.
9. Party Partially Traveled (Journey terminated short of destination).
10. Passenger Not Traveled As Reservation Provided In Lower Class.
11. Passenger Not Traveled Due To Ticket In RAC After Chart Preparation.
12. Passenger Not Traveled.
13. Train Canceled.
14. Train Diverted And Train Not Touching Boarding Station.
15. Train Diverted And Train Not Touching Destination Station.
16. Train Late More Than Three Hours and Passenger Not Traveled.
17. Train Missed As Connecting Train Was Late.
18. Train Terminated Short Of Destination.
19. Traveled Without Proper ID Proof.
20. Wrongly Charged BY TTE.