Preferred type is application/x-pkcs7-certreqresp
This mimetype is deprecated. You should still support it, but avoid using it to assign new mimetypes.
Instead, please use application/x-pkcs7-certreqresp
x-pkcs7-certreqresp and the .p7r extension were also introduced by Microsoft. Likely yet another alias for pkcs7-mime.
File types
.p7r
Also appears as
application/x-pkcs7-certreqrespPreferred
Further reading
Related to
No related mimetypes listed