P7S File - opening and understanding

Did your computer fail to open a P7S file? We explain what they are used for and recommend software that we know can open or otherwise handle your .P7S files.

What is a P7S file?

A .P7S file is a PKCS #7 Signature file. A P7S file is sent as an attachment to a digitally signed email message and contains the digital signature used to sign the email content.

Normally the attached file is called SMIME.p7s, where SMIME is short for Secure/Multipurpose Internet Mail Extensions. It is a standard used by email clients to handle digitally signed emails. The signature is used to verify the email's sender, to check that the email content has not been altered, and optionally to encrypt the email.

These files are also known as PKCS #7 signature files.

How to open P7S files

You will need a program compatible with the specific file you are trying to open, as different programs may use files with file extension P7S for different purposes.

While we have not verified the apps ourselves yet, our users have suggested 10 different P7S openers which you will find listed below.

Suggest another file format using extension P7S

While we know of one file format using the .P7S file extension, there may be more. It is widespread that different programs use files with the same file extension for very different types of data. Please let us know if you are aware of a different kind of .P7S file.

Various viewers for this file format

These apps are known to open certain types of P7S files. Remember, different programs may use P7S files for different purposes, so you may need to try out a few of them to be able to open your specific file.

InfoNotary e-Doc SignerInfoNotary e-Doc SignerUser submitted
DigiSignerDigiSignerUser submitted
P7S ViewerP7S ViewerUser submitted
DSToolDSToolUser submitted
digiSeal readerdigiSeal readerUser submitted
B-Trust Combo LiteB-Trust Combo LiteUser submitted
dikedikeUser submitted
EasySignEasySignUser submitted
SignVerifierSignVerifierUser submitted
LegalCert DiKeLegalCert DiKeUser submitted
We have not verified any software that we know for certain will work with P7S-files on Mac. If you know one, please use the 'Suggest a program' link below and tell us about it!
We have not verified any web services that we know for certain will work with P7S-files. If you know one, please use the 'Suggest a program' link below and tell us about it!