Received a e-mail with a p7m file as an attachment and you don't know what it is or how to read it? Under the circumstances I would say this tutorial of mine today happens to beans, as they say. With this article, in fact, I want to explain to you, in a simple but at the same time detailed way, how open files p7m. Happy?

Let's first try to understand what we are talking about. The p7m files are usually documents in which the electronic signature has been placed, which in Italy, together with the certified mail, legally supersedes the holographic signature and registered mail, for various reasons. It is a type of file generally used by professionals (architects, engineers, lawyers, etc.) and by officials of the Public Administration with the objective, in fact, of authenticating a text document or a project. With this in mind, opening the file type in question essentially means checking its validity and then reading its contents.

Yes but ... how to do it? Simple: use the online programs and services specifically designed for the purpose I have chosen to indicate below. All are quite simple to use, even for those who, a little like you, do not consider themselves a great computer expert, and they are free of charge. So? What about testing them? You? Come on then, let's not waste any more time chatting and get to work right away. I wish you, as always, a happy reading and I wish you great, indeed, very good luck for everything. Are you ready?

Programs for opening p7m files

As I said at the beginning of the article, to open files p7m can take advantage of some programs specially designed for the purpose in question. They are all (or almost) cross-platform, so you can take advantage of them on Windows, macOS, and Linux without any hassle and for free. For more information, keep reading, find more details about it below.


The first useful software to open p7m files that I want to count is dam. It is developed by InfoCert and allows the verification of documents already signed, as well as the digital signature on electronic documents (in fact, it is also supplied with digital signature kits). It has a very simple and intuitive interface and it is also quite easy to use. Can be used in Windows, Mac and Linux and is free.

To use it for its purpose, connect to the download page of the program and click the button Download what do you find in the logo operating system in use on your PC, to download it to your PC.

When the download completes, if you are using Windows, open the file DIke6-installer-win32.msi and click siguiente. Accept the terms of use of the software by selecting the item I accept the terms of the license agreement. and complete the configuration by clicking on siguiente twice in a row install en yes and in final

If, on the other hand, you are using a Mac, open the package.dmg just obtained and drag the Dike icon to the folder applications by macOS. Then right click on it and choose open twice in a row, to start the application, however, bypassing the restrictions imposed by Apple.

Now that, regardless of the operating system used, you will see the Dike window on the desktop, click the button Check twice in a row and select the reference file p7m. Alternatively, you can drag the file to be verified directly to the program window on the button Check. If you see an update notice appear for the list of certificates when you do so, you also accept the operation.

After completing the above steps, if the signature of the document you have selected is valid, you will see a sign of green tick followed by a special message and pressing the button details In the upper right you can see all the details related to the latter.

If the signature is invalid, a Red "x" Also, in this case, followed by an informational message and clicking the button report below you will learn the details of the error.

Aruba Sing

As an alternative to the above program, you can trust Aruba Sing to open your p7m files. It is software distributed by Aruba, as you can guess by the name itself, that allows you to verify and manage digital signatures (in fact, it is also included in the Aruba digital signature kit). It works on Windows, Mac and Linux and it's free.

To download it to your PC, connect to the program's download page, click on the wording ArubaSign signature software and press the button Download the software what do you find below operating system logo in use on your PC.

The download is complete, if you are using Windows open the file ArubaSign-xx.exe I just have it and click on yes and in good. Then press yes en siguiente twice in a row install and in final.

If, on the other hand, you are using a Mac, open the newly downloaded .dmg package and drag the program icon to the folder applications by macOS. Then right-click on it and select Open twice in a row, to avoid the limitations Apple imposes on non-certified developers.

At this point, regardless of the operating system in use, to open the p7m file in your possession, wait for the program to update the certificates and then click the button Check and select the file after clicking the button Select documents present in the displayed window. Alternatively, drag the latter directly onto the button to select documents.

Once this is done, in a few moments a window will open with the details of the signature included in the file you have selected and you can also find out if the latter is valid or not. It was easy, wasn't it?


MnlSignVerifier is another program you can trust to open p7m files. It is free software and is available only for OS Windows (both 32-bit and 64 bits) that acts in a good or bad way similar to the ones I have already mentioned. Therefore, you can consider it as a valid alternative to the tools mentioned above.

To download it immediately, connect to the download page. of the software and click on the link attached to the section instruments the correct version of Windows for your PC (eg. MnlSignVerifier - Digital Signature Verification Sw (32-bit) (38.8 MB) if you are using a 32-bit version of Windows).

When the download is complete, open the file MnlSignVerifier-setup_xxbit.exe I just have it and I click lo. Then press the button siguiente, select the article I accept the terms of the license agreement. and click again on siguiente seven times in a row finally press final.

Now start the program by double-clicking the relevant link that has been added to the desktop and hit the button Open file which is in the upper left part of the MnlSignVerifier window that has appeared. Then select the p7m file you want to open and wait a few moments for the program to process it.

Then you can see the sport returned by MnlSignVerifier and know all the details of the signature included in the file, as well as whether the latter is valid or not.

Online services to open p7m files

Don't want or can't download new programs to your PC but still need to open a p7m file? No problem.As anticipated at the beginning, specific web services are also used for the purpose in question. Listed below are those that in my opinion represent some of the best in the category. Put them to the test right away!


The first of the online services to open p7m files that I want palarti is Postcert. This is a solution offered by Poste Italiane, totally free and usable by any navigator and operating system without having to register. The only thing to keep in mind is that you can upload files with a maximum size of 50MB (which shouldn't be a problem for p7m files as they are generally much "lighter").

Do you ask me how to serve you? I'll show you right away. First, I linked to the home page of the service and clicked the button Choose file / Browse which is next to the entrance Select the file to verify:.

Then select the p7m file on your PC and click the button Verify signature you see appear below. Once this is done, in a few moments a new page will open with the result of the analysis and all the details related to the file you previously selected.

If you wish, you can also download the locally obtained report by clicking on the link Download report. If you have not made any changes to the default browser settings, the file will be saved in the folder Download of the Pc.


In addition to offering a software solution, InfoCert also offers users a convenient online service that makes it possible to open p7m files. The operation is good or bad analogous to that of PosteCert that I have indicated above.

To use it, connect to the service page, make sure the tab is selected at the bottom Digital signature verification (otherwise provide it) and then click the button Choose file / Browse, which is under the wording Select the file to verify:.

Then select the p7m file on your PC, click the button I accept and verify and wait a few moments to know the answer of the test.


Another useful online service for the purpose in question is the one made available by Namirial. Also in this case it is a free tool, which works from any browser and operating system and does not require any type of registry to be exploited.

To use it, connect to the website of the service and press the button Select File you find it in the section Verify signed or signed and marked documents and select the p7m file that you "host" on your PC and that you intend to open. Then press the button Check that you see appear below.

Wait a few moments for the service to process the file, after which you will be able to know the result of the document verification and you will be able to consult all the notes below.

Additional useful resources

In addition to the online programs and services that I told you about in my tutorial, there are also other tools that you can use to open p7m files. To get to know them all (and perhaps try them out), you can consult the corresponding list present on the website of the Italy digital agency. Look at it, I'm sure it can be of great help.