Is the woodhouse activity centre haunted house. When my client, federal government, sends me pdf attachments the files always appears as a smime.p7m file and will not open on my phone in Outlook. The same attachments appear as a standard pdf on my desktop and open as expected. My understanding is the secured signature within the pdf is causing the issue on the phone. Mar 20, 2018 P7S Viewer lets you view files signed by P7S Signer or other signature tool. It supports P7S/P7M signed email files and CMS web documents. It has a simple interface that lets you load supported files. You can view various details such as Issuer Name, Signature Time, Signature Algorithm, Signature Integrity, etc.
A P7S file is an email message that includes a digital signature. It can be used for sending secure emails that can only be viewed by the intended recipient. P7S files verify that the email is from who it claims to be from and that the email has not been modified in transit.
P7m File Viewer App
Most email applications, such as Microsoft Outlook, Apple Mail, and Mozilla Thunderbird, support digital signatures. However, if an email program does not handle digital signatures, a P7S file may appear as an attachment (smime.p7s) to the email message.
NOTE: Email programs that use P7S files use PKCS (Public-Key Cryptography Standard) #7 to sign email messages.