How can I tell whether Lightroom Classic is showing a cached preview when the original product photo is missing?

Illustrative exercise: separate preview from source

This is a fictional diagnostic exercise, not a report of testing Lightroom Classic. Imagine a product catalog containing two distinct images: a red mug photographed on white and a blue mug photographed on gray. The red-mug thumbnail remains visible after its test original is disconnected; the blue-mug original remains connected. Record what the catalog shows for each, but do not treat the red thumbnail as evidence that its full source is available.

Use the comparison to answer one narrow question: can you confirm the exact original file for the red mug? If not, stop its delivery workflow and locate the source first. The connected blue-mug photo is a reference for what an available original looks like in your own catalog, not a guarantee about particular editing controls or export results.

1. Use copies of the two exercise images and preserve the approved originals. Disconnect only the red-mug test copy for this exercise.
2. Compare the catalog’s visible preview with each photo’s original-file status. Note whether the catalog identifies the red-mug file as missing.
3. Pass condition: the red-mug original is identified as missing and held from delivery. Stop condition: if you cannot establish which original belongs to the photo, do not reconnect a guessed file or approve an export.

Read the file status, not just the thumbnail

Lightroom Classic catalogs and preview caches are distinct from source images. A cached thumbnail can remain viewable even when its original is no longer reachable. That preview can help you recognize a photo, but it cannot confirm that the original file is present for the work you intend to deliver.

Check whether Lightroom Classic marks the photo or its folder as missing. Before choosing a location, check whether an external or offline drive simply is not connected, and confirm the exact original’s identity. A matching-looking thumbnail or filename alone is not enough to justify linking the wrong product image.

1. If the photo is marked missing, pause editing and export decisions for that asset.
2. Check for an offline drive, then compare the candidate original with the intended product photo.
3. If status or identity remains unclear, keep the asset on hold rather than treating the preview as a deliverable.

Reconnect with the matching control

For an individual missing photo, use Locate to reconnect the catalog entry to its original. For a missing folder, use Find Missing Folder to reconnect the folder. These controls address different scopes: choose based on whether the missing item is one file or a folder.

After reconnecting, confirm that the file is the exact intended original, not merely another image of the same product. This identity check is the decision point: when it succeeds, continue with your normal asset review; when it fails, stop and keep the item out of delivery.

1. One missing photo: use Locate and select the confirmed original.
2. Missing folder: use Find Missing Folder and select the confirmed folder.
3. Confirm the intended product and source before resuming work. If the match is uncertain, do not approve the asset.

Apply the delivery gate

For product-photo handoff, use a simple editorial gate: a visible preview is not approval; a confirmed, reachable original is a prerequisite for treating the asset as ready. This recommendation is a workflow safeguard, not a claim about which Develop controls remain active or what Lightroom Classic will do when exporting a missing original.

If you cannot reconnect and identify the original, mark the asset as blocked and request the source file. Do not solve a missing-file warning by deleting the catalog or reimporting everything: catalogs can contain work not saved to photo files, and a new catalog starts empty. Keep the approved original and make any diagnostic changes on a test copy.

Use this question’s review worksheet

The sample rows are fictional exercise data. Preserve the example, save a working copy and record your own inputs, observations and decisions. The example is not a test receipt.

Fictional manual source-check worksheet (CSV)