I face difficulties when I want to sign an Excel vba project. The error "A problem occured with the digital certificate. The VBA-project can't be provided by a digital signature. The signature is being removed". We are using an USB key of DigiCert (EV code signing with SHA2 encryption) and signing works correctly for exe's and dll's. Everything looks okay from DigiCert point of view.
The error does occur when I want to save the Excel file.
I can sign without problems when it is a self issued certificate.