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# Invoice Duplicate Check

With the automatic duplicate check in invoices, you can quickly see if an invoice already exists, either exactly the same (e.g., received via email) or with slight changes. The system performs the duplicate check in two stages: first when receiving the file via email, and again during manual entry in the Invoice Inbox.

### **Duplicate Detected via Email Submission**

When a PDF invoice is sent to the DPO invoice email address (e.g. .dpo-xxxxx@dpo-import.com), the system automatically checks if the same file has already been submitted.

###### What happens if a duplicate is detected?

* If the **file name** and **file content** match an already-processed invoice, the system blocks it.
* You will receive an **automatic email notification** from do-not-reply@digitalpurchaseorder.com.
* The email clearly states the file is a duplicate and was not processed again.

**Example message:** “File: Nexus_INVOICE_TESTAP_EUR_235596013.pdf was already processed and is a duplicate.”



![](https://storage.crisp.chat/users/helpdesk/website/-/7/e/f/8/7ef8b3dbb012a000/image_1jcymbn.png =916xauto)




### **Duplicate Check During Manual Entry**
If the same invoice is submitted again, but the file was slightly modified (e.g., renamed or edited), the PDF will still reach the **Invoice Inbox**. Here, DPO performs a second-level duplicate check based on invoice content.

**Step 1: If the Invoice Number** already exists for the **same supplier**, a warning appears: 
* “This number already exists on an invoice from the same supplier. Click to compare.”

**Step 2: By clicking “Click to compare”**, a **side-by-side comparison** opens, showing:
* The current invoice from the inbox flagged as a potential duplicate
* The previously processed invoice

**Step 3:** Review both invoices visually.
* If they are truly different (e.g. one is corrected), you can **confirm "It's not a duplicate"** and proceed.
* If it’s indeed a duplicate, you can choose to "Delete this duplicated invoice" from the Inbox.

|| The duplicate detection is based on both metadata (Invoice Number, Supplier) and PDF content structure.


![](https://storage.crisp.chat/users/helpdesk/website/-/7/e/f/8/7ef8b3dbb012a000/screenshot-2026-04-29-at-09265_5z9oc0.png =1042xauto)




${color}[#0d5068](**Questions or need help?**)
*Our customer support is always available to help with any questions or setup assistance*

**Contact us**
**Email**: [support@digitalpurchaseorder.com](mailto:support@digitalpurchaseorder.com)
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