We would liek to use a certificate in the certificate store in order to sign a PDF.
Actually we are using an ExternalSignature created with an X509Certificate2 by opening our certificate in our store.
We are facing a problem with the signed PDF because it does not contain the certificate chain and then Adobe PDF does not show the signature as valid.
Using the same certificate but from a .pfx file instead of loading the certificate from the store, everything is ok.
Can you help?