Bulk-Importing Vehicles from a Spreadsheet: Stock Number + VIN Matching, Stalled Uploads, and Undo Last Import

This article covers the CSV Import Tool under Setup > Inventory — specifically its duplicate-matching rule, which only recognizes a vehicle you already have if the spreadsheet row carries both the exact Stock Number and the exact VIN. If either is missing, Import Inventory creates a second vehicle record instead of updating the existing one.

Scope: this article is only about the CSV Import Tool for vehicles. It is not about the DeskManager 11 or Frazer migration path (see DeskManager (Desktop) Import Log), not about vehicles arriving from WebManager, and not about duplicate contacts — contact duplicate matching is a different feature with different rules.

Questions this answers

• "How do I import 200 vehicles with the CSV Import Tool without creating duplicate stock numbers?"
• "My CSV Import Tool upload of 150 cars stopped part way through the row count. Are the rows before it already saved as vehicles, or do I re-upload the whole file?"
• "Is there an Undo Last Import for the CSV Import Tool if I mapped the columns wrong?"
• "My inventory spreadsheet has a VIN column but no Stock Number column. Will the CSV Import Tool still match cars already in my inventory?"
• "Is there a CSV Import Tool for contacts, the way there is for vehicles?"

Before you start

Go to Setup > Inventory > CSV Import Tool. The tool accepts a .csv file only — there's no built-in upload for Excel (.xlsx) files, so save your spreadsheet as CSV first.

There is no fixed required-column template. After you upload the file, you tell the tool which row is the header, then map each of your spreadsheet's columns to a vehicle field using a dropdown next to that column. The fields you can map include Stock Number, VIN, Inventory Date, Make, Model, Year, Mileage, Exterior/Interior Color, Body Style, Vehicle Type, Purchase Cost, Purchase Vendor, Purchase Date, Asking Price, Internet Price, Pack, and several others. If you saved a column-mapping preset from a previous import, it will only auto-fill for a new file if that file's header text matches the saved preset's headers exactly.

How duplicate detection works — you need BOTH Stock Number and VIN

This is the part that causes accidental duplicates. When you click Import Inventory, each row is checked against your existing inventory, but only if both a Stock Number and a VIN are mapped and filled in on that row. If both are present, the tool looks for an active vehicle with that exact Stock Number and that exact VIN already on file. Only then does it update the existing vehicle instead of creating a new one.

That means:

• VIN alone is not enough. If your spreadsheet has the VIN column but no Stock Number column (or the cell is blank), the row will never match an existing vehicle — DeskManager Online creates a brand-new vehicle record every time, even if the same VIN already exists in your inventory.
• A close-but-not-exact match doesn't count. A different or blank Stock Number on an otherwise-matching VIN also results in a new vehicle, not an update.
• The match isn't limited to your current lot. The check looks across your whole account, not just the lot you're currently working in — so a matching Stock Number and VIN can update a vehicle sitting on a different lot than the one you expect.
• Only active vehicles are matched. A sold or deleted vehicle with the same Stock Number and VIN won't be found, so re-importing it creates a new record.

To bring in a large batch (for example, 200 vehicles) without creating duplicates: make sure every row includes both an accurate Stock Number and VIN before you import, and don't leave either column blank for vehicles you already have on file.

VIN decoding also runs automatically on each new vehicle and can fill in or overwrite Make/Model/Year/Style even if you didn't map those columns, unless the row is flagged as a non-decodable vehicle type.

If the upload stops partway through

Rows are sent to the server and saved one at a time, in order — not as a single all-or-nothing batch. If one row's request fails partway through a large import, the tool has no visible error message for that failure; the screen simply stops advancing.

What that means for your data:

• Every row processed before the stop is already saved as a real vehicle. There's no automatic rollback.
• Every row after the stop was never attempted.
• Nothing on screen tells you which row it stopped on.

What to do: check your Inventory List, sorted or filtered by date added, to see exactly which vehicles from your file actually saved. Compare that against your spreadsheet to find where it left off, then re-upload only the remaining rows — mapped the same way — to finish the batch. Don't just re-run the whole file, since anything already saved could create a duplicate if the re-run rows are missing their Stock Number or VIN.

Undoing or recovering from a bad import

If your column mapping was wrong and the import created a batch of bad vehicle records, self-serve undo depends on a setting your AutoManager support team controls.

• If your account has the CSV import undo/history feature turned on, the CSV Import Tool page shows a History tab next to the CSV tab, with a before/after comparison table and an Undo Last Import button. Clicking it restores what previously existed before your last import and deletes any new vehicles that import added.
• If you don't see a History tab, this feature isn't enabled for your account yet. There's no other self-serve way to bulk-reverse an import — you'll need to manually edit or delete the incorrect vehicle records from the Inventory List, or contact AutoManager support to ask about enabling the undo feature.

Is there a bulk import for contacts too?

No. The CSV Import Tool is built for vehicles only — there's no equivalent spreadsheet upload for adding or updating contacts in bulk. To get a large number of new customers into DeskManager Online, you'll need to add them one at a time, bring them over as part of a DeskManager 11 migration or let them sync in through WebManager.

When to contact support

Reach out to AutoManager support if:

• You need the CSV import undo/history feature turned on before running a large import.
• An import created duplicates spanning multiple lots and you need help identifying which vehicles are safe to delete.
• You're migrating a full inventory and vehicle history from a legacy system — see DeskManager (Desktop) Import Log for that process instead of the CSV tool.