Image
What is a .p7m file?
A .p7m file is a PKCS #7 Cryptographic Message File. This is an image format — a picture, drawing or graphic.
How to open a .p7m file
- GIMP (free) and IrfanView open a very wide range of image formats, including obsolete ones.
- XnView MP is the best bet for unusual or legacy image types.
- Your operating system's built-in viewer may work for mainstream formats.
The registry records this extension against PKCS #7 Cryptographic Message File, so software from that family is the most likely match.
How to convert a .p7m file
- Open it in GIMP or XnView and export as .png (lossless) or .jpg (smaller).
MIME type
When a .p7m file travels over the web, servers label it with one of these MIME types:
application/pkcs7-mimeapplication/pkcs7-signatureThe technical record
For archivists, developers and the merely curious: these are the PRONOM registry entries for .p7m.
| Format name | Version | MIME type | PUID |
|---|---|---|---|
| PKCS #7 Cryptographic Message File | — | application/pkcs7-mime, application/pkcs7-signature | fmt/670 |