Once you have a Corrupted Key Code, make your way through the Expunge mission and kill the boss. Once it's destroyed, approach the chest in the center and open it up to receive a piece of gear and some Decrypted Data.
How much decrypted data do you get from expunge?
This Decrypted Data farm should allow you to get about 1500 Decrypted Data per hour. To get the data, you need to complete Override or Expunge missions. For this method, we will be doing a specific Expunge mission.
Can I still get decrypted data in Destiny 2?
At the moment there are four different methods to get Decrypted Data: Complete certain Season of the Splicer storyline quests. Complete Seasonal Challenges. Open Conflux Chests in Override (this seasonal activity requires the season pass)