• You selected a drive and clicked “Rebuild”
  • Controller began syncing or rebuilding
  • Suddenly: RAID 5 now shows “Offline” or “Virtual Disk Missing”
  • The controller tried to write parity to a wrong or misordered disk
  • An undetected second failure may have existed
  • A power loss or sync conflict corrupted the config mid-process
  • 🚫 Don’t retry the rebuild again
  • 🚫 Don’t replace the same drive and try again
  • 🚫 Don’t start clearing or recreating arrays

The RAID controller doesn’t know which config is correct — it’s relying on you. A wrong guess during rebuild can overwrite valid parity with junk.

This is one of the most common triggers for full data loss in RAID 5: a rebuild was initiated on the wrong member. It’s almost never salvageable after two or more rebuild attempts. But if you stop now, we can still recover and save your files.