Spotlight problems

Spotlight and external drives

Updated 2026-07-31 · 6 min read

Spotlight's index is per-volume. Eject a drive and everything it knew about that drive is gone from search — not archived, gone. For anyone with an archive disk or a backup drive, that is the single most frustrating thing about macOS search.

Why it happens

Every mounted volume gets its own index store, kept on the volume itself in a hidden .Spotlight-V100 folder. Unmount the volume and the store goes with it. Spotlight has no memory of drives that are not currently attached, by design.

This is defensible engineering and terrible ergonomics. The question people actually ask — *"was that project on the Samsung drive or the LaCie?"* — is unanswerable without plugging both in and searching each.

Check whether the attached drive is indexed at all

mdutil -s /Volumes/YourDriveName

If it reports indexing disabled, enable it:

sudo mdutil -i on /Volumes/YourDriveName

And if results are still wrong, rebuild that volume specifically:

sudo mdutil -E /Volumes/YourDriveName

Common reasons an attached drive still will not index

• The drive is formatted exFAT or FAT32. These are cross-platform formats without

the metadata support Spotlight relies on. Indexing is unreliable at best. APFS or Mac OS Extended index properly.

• The drive is read-only. Spotlight needs to write its index onto the volume.

NTFS drives mounted read-only cannot be indexed.

• It is in the Privacy list. Check System Settings → Siri & Spotlight → Spotlight

Privacy. Drives get added there by accident.

• It is a network share. Only servers that explicitly support remote indexing work,

and most consumer NAS boxes do not.

Searching a drive that is not plugged in

macOS cannot do this. The honest workaround people use is to keep a text catalogue: mount the drive, run something like

find /Volumes/Archive -type f > ~/Documents/archive-catalogue.txt

and then search that text file later. It works, and it is exactly as tedious as it sounds.

The alternative is an index that keeps records for volumes after they are unmounted and marks them unavailable rather than deleting them, so the drive's contents stay searchable and each result tells you which disk to go and fetch. That is how Everywhere handles it — an unplugged drive's files still appear, dimmed, labelled with the volume they live on.

Common questions

Why does my external drive index only sometimes?

Most often the format. exFAT and FAT32 lack the metadata Spotlight needs; APFS and Mac OS Extended (HFS+) index reliably.

Can I stop macOS indexing an external drive?

Yes — sudo mdutil -i off /Volumes/Name, or add the drive to the Spotlight Privacy list in System Settings.

Does Time Machine's backup drive get indexed?

Backups are excluded from normal Spotlight results deliberately, which is why you cannot search your Time Machine disk like an ordinary volume.