Fix a problem
Start with the symptom. Each page has one first action, then a stop condition.
iOS 27 Battery Drain — Has Indexing Finished?
Screen-on time collapsed after installing iOS 27. Settings may show search and Siri still optimizing. Reddit threads ask this before any other diagnosis.
TROUBLESHOOTINGUpgrade to iOS 27 Still Shows iOS 26.7
Software Update lists iOS 26.7, plus an “Also Available” / Upgrade to iOS 27 row. Tapping 27 opens a large 26.7 download. Launch-week r/ios threads treated this as a UI bug, not a missing update.
TROUBLESHOOTINGiOS Software Update Not Showing on iPhone
Settings → General → Software Update says your iPhone is up to date, but a newer iOS version has already been released.
TROUBLESHOOTINGUnable to Verify Update on iPhone
The download finishes, then iOS reports that it cannot verify the update.
TROUBLESHOOTINGiPhone Storage Full and Cannot Install iOS Update
Software Update refuses to download or install because there is not enough free space.
TROUBLESHOOTINGiPhone Won’t Update to the Latest iOS
Download and Install fails, loops, or never starts even though the update is listed.
TROUBLESHOOTINGiPhone Update Stuck on Preparing or Estimating Time
The installer sits on Preparing Update or Estimating time remaining for far longer than a normal install.
TROUBLESHOOTINGiPhone Update Error 4013
Finder, Apple Devices, or iTunes reports error 4013 while updating or restoring.
TROUBLESHOOTINGiPhone Update Error 4014
A computer restore or update stops with error 4014.
TROUBLESHOOTINGiPhone Restore Error 9
Restore stops with error 9.
TROUBLESHOOTINGiPhone Restore Error 14
Restore fails with error 14 while writing firmware.
TROUBLESHOOTINGBattery Drain After an iOS Update
Battery percentage falls much faster in the first days after installing a new iOS version.
TROUBLESHOOTINGiPhone Overheating After an iOS Update
The iPhone feels hot at idle or while charging in the first days after updating.
TROUBLESHOOTINGApps Crashing After an iOS Update
One or more apps close immediately after you update iOS.
TROUBLESHOOTINGWi-Fi or Bluetooth Problems After Updating iOS
Wi-Fi drops, Bluetooth accessories forget pairing, or cellular and Wi-Fi fight after the update.
TROUBLESHOOTINGiPhone is Disabled, Connect to Computer
The lock screen says the iPhone is disabled and asks you to connect to a computer.
TROUBLESHOOTINGCannot Install Update: Insufficient Space
iOS shows insufficient space even after you deleted photos or apps.