Defend

Defend Settlement is a Minutemen radiant quest in Fallout 4.

Quick walkthrough
While playing you are notified via on screen text that a settlement needs your help defending it. On arrival you find it under attack, after a successful defense a settler will thank you and initiate a short conversation.

Detailed walkthrough
Your settlement can come under attack from one of several different groups: Super Mutants, Ghouls, Synths, Raiders, and Gunners. Simply killing them is all you need to do.

Bugs

 * Sometimes the quest doesn't complete.
 * Search inside and outside of the settlement for enemies that have not been killed and kill them.
 * Open the console. Target a dead enemy (by clicking on their corpse). enter the command . Exit console. Kill the resurrected enemy. This will help in case the kill-counter is missing a kill.
 * If after killing a wave of synths and with no further attacks you find the quest will not complete then open the console with "`" and select a synth then enter the command . After the synth dies the quest should complete.
 * If on arrival you find your settlers have killed a synth infiltrator you may also find there is no attack incoming. Open the console with "`" enter the command . The quest will complete.