CryptoAPI (CAPI)

What it is

CryptoAPI (CAPI) is an application programming interface that enables application developers to add authentication, encoding, and encryption to Windows-based applications.

Microsoft is slowly leaving CAPI in favour of CNG. We have seen it happen in outlook.exe and in some .Net Framework scenarios from version 4.7.2.

Developing with CAPI

Start here: https://docs.microsoft.com/en-us/windows/win32/seccrypto/cryptography-portal

Some advices

# Avoid working with cards
# Avoid working with containers
# Avoid working with labels
# Avoid working with keys

Just go for the certificates in Mystore

The CSP

You cannot see who's taking care of your certificates in Mystore via the certificate snap-in:

To find out what CSPs handling your certificates in Mystore type:

certutil -store -user MY

In this case we can see that the certificate in the picture above is registered by "Net iD - CSP":