Is your signing certificate in the Windows Certificate Store or in the Acrobat Digital IDs store? I saw posts that Acrobat X does not process correctly certificates in the Windows Certificate Store. Try to add your certificate to Acrobat's digital IDs and try to sign with this certificate.
Thanks for the reply. Yes it is a Windows Certificate Store. It is from our internal PKI environment. What do you mean by adding my certificate to Acrobat's digital ID? Can you give me an example?
I did download a trial of Acrobat DC and my cert works fine there. I was hoping there would be a fix for Acrobat X pro since we already own that product.
You should have the original certificate file (.p12 or .pfx) which you (or someone on your behalf) imported into the Windows Certificate Store. You can import the same file into Acrobat's Digital IDs. In X, you go to Tools->Sign&Certify->More Sign&Certify->Security Settings dialog. Select Digital IDs in the left pane and click "Add ID" button on the top of the right pane.