---
id: KB-SC-010
url: https://app.codecontract.io/help/smartcheck/what-to-do-if-verification-fails
idioma: en
categoria: smartcheck
subcategoria: compartir
audiencia: usuario
nivel: intermedio
actualizado: 2026-08-13
tambienEn: [es]
relacionados: [KB-SC-005, KB-TZ-002]
citadoPor: [KB-SC-013]
---

# If verification says it does not match

_It is almost never fraud. The four real causes, by frequency._

**Responde a:** verification says it does not match · the document will not verify · error verifying a document · the hash does not match what does it mean

It says "does not match" and the first instinct is to think someone tampered with the document. It is almost never that. These are the four real causes, and fraud is the least frequent.

| Cause | How to spot it | What to do |
| --- | --- | --- |
| The file was reprinted or re-saved | It looks the same, weighs differently | Ask the sender for the original |
| It was converted to another format | The extension changed | Ask for the original in its format |
| It came from a much-forwarded email | Usually with a changed filename | Request it from source |
| It is a different document | Here it is worth asking | Check with whoever issued it |

> [!IMPORTANT]
> The first three are things anyone does without ill intent: opening a PDF and saving it from another program modifies it even if the content looks identical. Before raising a suspicion, ask for the original file — it resolves ninety per cent of cases.

## How to ask for the original without accusing

"The file is not verifying for me — it has probably been re-saved along the way. Could you send me the original exactly as it reached you?" achieves the same as a suspicion and breaks nothing if, as is likely, there was nothing to suspect.

## When to be concerned

**En corto**

- The sender sends the same file twice and it still does not verify.
- The document says something different from what you remember agreeing.
- And it arrives urgently, through an unusual channel, from someone you were not expecting.

> [!WARNING]
> If all three coincide, do not treat it as a technical problem. A document that fails verification, says something different and arrives urgently through an odd channel is the pattern of an impersonation: phone the number you already had before acting on it.

> [!NOTE]
> "Not found" is different from "does not match". Not found means that document was never sealed here: it may be from another issuer, or simply not certified.

**Can I find out what changed?**

No. The fingerprint says it changed, not what.

**What if the original does not verify either?**

Then yes, check with whoever issued it.

**Does a scanned printout verify?**

No. It is a new file, even if the content is identical.

## Ejemplos

**A client reports that a certificate you sent does not verify.**

- Asks for the file exactly as they received it
- Finds they had re-saved it from their email client

→ Resolved in five minutes without anyone raising a suspicion that was never warranted.

**The file was opened and re-saved.**

- Checks against the untouched original copy

→ Verification comes out correct.

**A file converted to another format is checked.**

- Verifies the file exactly as sealed

→ The conversion stops looking like tampering.

**It is compared against a different version of the document.**

- Confirms which version was sealed

→ Like is compared with like.

**The file arrived through a channel that recompresses it.**

- Requests it again uncompressed

→ The fingerprint matches again.

**It genuinely does not match and there is no explanation.**

- Documents the check and escalates

→ The case is handled with the trail in view.