# How to open a P7M file (digitally signed document)

> A .p7m file is a document with a digital signature inside an "envelope". To read it you need a free verification program, from those listed by AgID, or the online verifier of the Italian notaries. Here is how, and what to keep.

Source: https://simplebuild.it/tutorial/aprire-file-p7m
Author: SimpleBuild, Build simple. Deliver value.
Category: PDFs and documents
Procedure verified on: 2026-09-30

A file that ends in **.p7m** (for example `contratto.pdf.p7m`) is a document with a **digital signature**. The real document, the PDF, sits inside an "envelope" together with the signature, so it does not open with a double-click like a normal PDF. You need a **verification program**: there are free ones, listed by Italy's digital agency, AgID (Agenzia per l'Italia Digitale). As an alternative you can use the **online verifier** of the Italian National Council of Notaries (Consiglio Nazionale del Notariato).

## Before you start

- **What a P7M is.** According to the guide to digital signatures published by AgID, when a document is signed the file keeps its name and gets the extra extension "p7m": `mensa.pdf` becomes `mensa.pdf.p7m`. Italian public administrations are required to accept this format.
- **You don't need a smart card, a reader or a digital signature of your own.** The right program is enough to read and verify a signed document.
- **Keep the computer connected to the internet.** The program uses the network to check whether the signer's certificate has been suspended or revoked. Offline you still see the document, but that check is missing.
- **Never throw away the original .p7m file.** That is the one with legal value. The file you extract is for reading and printing.
- **If the P7M came by email from a stranger**, stop: first read [how to spot a phishing email](https://simplebuild.it/tutorial/riconoscere-email-phishing).

## What the verification program checks

The AgID guide explains that verifying a digital signature checks four things:

1. that the document **has not been changed** after it was signed;
2. that the signer's certificate is backed by a recognized **certification authority**;
3. that the certificate **has not expired**;
4. that the certificate **has not been suspended or revoked** (this is why you need the internet).

If all four checks pass, the signature is valid and you know for certain **who** signed.

## On Windows: with a free program from the AgID list

AgID publishes a page, **Software di verifica** ("Verification software"), with the programs that vendors make available **free of charge** to verify signatures and open signed documents. Any program on that list will do. The page was last updated on September 29, 2021: if a link no longer works, look for the program on the vendor's website.

One of the programs on the list is **DigitalSign Reader** by CompEd, for Windows. The vendor says it is free for private individuals who do not use it professionally, and that it opens signed documents (including the CAdES format, that is .p7m files), lets you view, print and export their content, and verifies the signature. After installation it asks for a **registration** and license activation: read the terms before you accept. The program and its website are in Italian.

The steps, in the form described by the AgID guide (button names change from program to program):

1. Install the verification program, downloading it **only** from the vendor's official website, which you can reach from the AgID page.
2. Open the .p7m file with the program: usually a **double-click** on the file is enough, or a right-click and the program's verify option.
3. Read the **verification report**: it tells you whether the signature is correct, who signed and whether the certificate is valid.
4. Use the option to **save the document**: the program asks where to save it and creates the copy without the signature, for example the PDF, which you open as usual.

## On Mac, iPhone and Android: with the online verifier

On these systems the simplest way, with nothing to install, is a verifier that runs in the browser. The AgID page lists a few; one is the **Verificatore On Line (VOL)** ("Online Verifier") of the National Council of Notaries, which according to the notaries recognizes the signatures and time stamps of certifiers accredited by AgID and of European trust service providers. The page is in Italian.

1. Open the page [vol.ca.notariato.it](https://vol.ca.notariato.it/it) in your browser.
2. Choose **Scegli un file firmato...** ("Choose a signed file...") and select the .p7m file.
3. Press **Verifica** ("Verify") and wait for the answer.

**Be careful with online verifiers.** To work, they **upload your document to a server** somewhere else. For an ordinary document that may be fine; for medical reports, contracts, ID documents or other people's data, a program on your own computer is better. The same goes, even more so, for unknown sites that promise to "convert" P7M files: you don't know where your file ends up. The European Commission, too, warns on the demo page of its verification service (DSS) that files are sent to its systems, asks you not to upload documents with sensitive data and says it should be used for testing only.

If you often receive P7M files on your Mac or phone, the AgID list includes programs from various vendors: check each vendor's website to see which systems it supports.

## If it still doesn't work

- **The program says the signature is not valid, or the certificate has expired or been revoked**: you can still read the document, but the signature may have no value. Ask the sender to check it or to send it again.
- **The verifier says the file is not signed or is damaged**: the file may have been corrupted during the download. Download it again from the email or the [PEC](https://simplebuild.it/tutorial/pec-come-funziona) (Italian certified email) and try again.
- **The file ends in .p7s instead of .p7m**: it is a "detached" signature. In the notaries' verifier, upload the signature file in the first field and the original document in the **Carica documento originale...** ("Upload original document...") field.
- **After opening it you have to sign a document yourself**: see [how to sign a PDF](https://simplebuild.it/tutorial/firmare-pdf).
- **The extracted PDF is too heavy to forward**: the guide on [how to reduce the size of a PDF](https://simplebuild.it/tutorial/comprimere-pdf) can help, but remember that the legal value stays with the original .p7m.
- If your work involves receiving many signed documents, invoices or deeds to file, a technician can set up the verification program once and for all, plus a tidy folder to keep them in.

## Frequently asked questions

### Can I open a P7M by removing the extension from its name?

No, that is not the right way: the file is still an "envelope" with the signature inside, and an ordinary program cannot read it. Use a verification program: it shows you the document and also tells you whether the signature is valid.

### Do I need my own digital signature or a smart card reader to open a P7M?

No. To verify and read a signed document you need neither the smart card nor the reader: a verification program or an online verifier is enough.

### After opening it, which file should I keep?

Keep the .p7m file you received. It is the one that contains the digital signature and has legal value; the extracted copy (for example the PDF) is only for reading and printing.

### Does a digitally signed PDF open the same way?

A PDF signed in the PAdES format is still a PDF and opens with a normal PDF reader. A .p7m file uses the CAdES format instead, and needs a verification program.

## Sources

- [Verification software, AgID (in Italian)](https://www.agid.gov.it/index.php/it/piattaforme/firma-elettronica-qualificata/software-verifica)
- [Qualified Electronic Signature (AgID)](https://www.agid.gov.it/en/platforms/qualified-electronic-signature)
- [Guide to the digital signature, CNIPA 2009, AgID (in Italian)](https://www.agid.gov.it/sites/default/files/repository_files/linee_guida/guida_alla_firma_digitale_2009_a_0_0_0.pdf)
- [Certification Authority of the National Council of Notaries (in Italian)](https://ca.notariato.it/ca/)
- [Online Verifier VOL, National Council of Notaries (in Italian)](https://vol.ca.notariato.it/it)
- [DigitalSign Reader, free software, CompEd (in Italian)](https://comped.it/software-gratis)
- [DigitalSign Reader 5.0, download and terms, CompEd (in Italian)](https://comped.it/firma-digitale/edizioni/digitalsign-reader-5-scaricalo-subito)
- [DSS Demonstration WebApp (European Commission)](https://ec.europa.eu/digital-building-blocks/DSS/webapp-demo/home)