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What should you open .p7s files with?

Anonymous
2010-10-09T04:04:11+00:00

I have no idea if I am in the right forum or what half of this stuff is. I just want to get a recommendation of what software to use to open a .p7s file from a trusted source. There seems to be a lot of sites out offering a free download of a .p7s viewer, and many of them lead a web surfer to a half dozen other free downloads of magic files that speed up your computer by 300% or other fantastic promises without ever finding the desired download. Is there a trusted site where I can find this software without having to worry about viruses and over the top advertising efforts?

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  1. Anonymous
    2010-10-09T04:17:31+00:00

    I have no idea if I am in the right forum or what half of this stuff is. I just want to get a recommendation of what software to use to open a .p7s file from a trusted source. There seems to be a lot of sites out offering a free download of a .p7s viewer, and many of them lead a web surfer to a half dozen other free downloads of magic files that speed up your computer by 300% or other fantastic promises without ever finding the desired download. Is there a trusted site where I can find this software without having to worry about viruses and over the top advertising efforts?

    Hi

    Where are you seeing these files with a p7s file extension? If these are files that you received from a trusted source, I would get in touch with that source and ask them how to open the files.

    Here is a description I found.

    p7s File Description:

    S/MIME (Secure/Multipurpose Internet Mail Extensions) provides a consistent way to send and receive secure MIME data. Based on the popular Internet MIME standard, S/MIME provides the following cryptographic security services for electronic messaging    applications: authentication, message integrity and non-repudiation of origin (using digital signatures) and privacy and data security (using encryption).

    Hope this helps.

    Thank You for using Windows 7

    Ronnie Vernon MVP

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  1. Anonymous
    2016-10-02T00:39:12+00:00

    Hi,

    This is a areally old thread. I can't believe that it has not yet been properly answered from a microsoft representative.

    This is a Microsoft Outlook format as far as I have found on the internet.

    So as a Microsoft software user I would expect that Microsoft either provide proper information about the format so that people don't have to ,as the thread creator and I both feel, use third party unverified softare; or simply use another format.

    Could you please provide a proper answer so  that other people searching the net will get this answer from Microsoft (or even a Microsoft MVP) instead of softopia nad cnet and other untrusted sites.

    Regards

    Niclas Carlstedt

    Hi

    This is not just a Microsoft file format, it is used by dozens of full featured email programs.

    There is a good description of this file format on the following website.

    What Is the .P7s File Extension?:

    https://www.techwalla.com/articles/what-is-the-p7s-file-extension 

    If you see a P7s file extension in your email, someone's sent you a digitally signed document. When someone sends you an important document, the digital signature confirms the sender's identity and the document's authenticity. The P7s extension shows up if your email program can't handle digital signatures.

    Digital Signatures

    Using digital signatures requires both public and private encryption keys. The person sending you the email creates a hash -- a mathematical summary -- of the contents and encrypts it with his private key. When you receive the email, you make a second hash, then decrypt the sender's hash with your public key. If the two hashes match, the document is authentic and hasn't been tampered with.

    The P7s

    To open a P7s you need an email client that works with Public Key Cryptography Standard No. 7. These programs include Thunderbird, Outlook, Apple Mail and Post Box. If your email client doesn't handle PKCS 7, you see the smime.P7s attachment. The attachment only contains the hash so you don't need to open it to read the document. However, you might want to check with the sender to verify what he sent.

    Regards

    5 people found this answer helpful.
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  2. Anonymous
    2016-10-01T09:00:10+00:00

    Hi,

    This is a areally old thread. I can't believe that it has not yet been properly answered from a microsoft representative.

    This is a Microsoft Outlook format as far as I have found on the internet.

    So as a Microsoft software user I would expect that Microsoft either provide proper information about the format so that people don't have to ,as the thread creator and I both feel, use third party unverified softare; or simply use another format.

    Could you please provide a proper answer so  that other people searching the net will get this answer from Microsoft (or even a Microsoft MVP) instead of softopia nad cnet and other untrusted sites.

    Regards

    Niclas Carlstedt

    5 people found this answer helpful.
    0 comments
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