Samsung Galaxy Duos (GT-I8262D) Firmware Overview
What is the latest GT-I8262D firmware?
I8262DZCAMJ1, released October 29, 2013 with Android 4.1. The archive holds 2 official builds across 1 region (CSC). Each one is the full stock ROM (flash file) for Odin, not an OTA patch.
Is the Samsung Galaxy Duos still getting updates?
Most likely not: there has been no new firmware since October 2013, so Android 4.1 is the last version this model got. The final builds below are still the best choice for a clean reinstall.
All GT-I8262D firmware builds
How to Flash GT-I8262D Firmware
Put the Samsung Galaxy Duos into Download Mode, load the BL, AP, CP and CSC files into Odin on a Windows PC and press Start. Use HOME_CSC to keep your data, CSC for a full wipe.