What your India Post status means
India Post wording varies a little between services, but most statuses fall into these stages.
The usual stages
Booked / Registered — the article was accepted at the counter and a consignment number was issued.
In transit / Bag received / Dispatched — it is moving between sorting hubs. Each scan is a handover point.
Reached delivery office / Out for delivery — it is at your local post office and expected with the delivery staff that day.
Delivered — handed over. If it is a high-value item, the delivery staff record the recipient details.
The ones people ask about
Delivery attempted / Unsuccessful — the postman reached the address but nobody could receive the article. It usually goes back to the delivery office for another attempt.
Returned to sender / RTO — the article is travelling back to whoever booked it, normally after failed delivery or an address problem.
Status not found — the number has not been scanned yet, or it was entered with a typo. Numbers take some hours to appear after booking.