Solve this problem On the client side: 1 - Using Internet explorer 8 2 - Import and install, CA Certificate Chain 3 - Import and install, Certificate Revocation List On the server side: After approve an application for registration certificate Update Certificate Revocation List (CRL) After doing this, I could import my certificates and sign word documents and pdf without problems. He was using DogTag Certificate System 1.3, I have now installed the version 10.