Unable to digi sign adobe form, get error 2148532255 The windows cryptographic ervice provider reported and error an unexpected card error has occurred.

I have multiple users who are using Adobe Acrobat10 or 11.0.2 with Windows 7 and Active Client Agent SHA1 Hash to sign Adobe forms. Just recently (2 weeks) they have been getting pop ups asking if they are ok with down grading their signature hash to SHA1 rather than SHA256. When they click continue it signs and saves. It has progressed now to give me the error "The windows cryptographic service provider reported an error: An unexpected card error has occurred, 2148532255. I have no back ground on this issue. Please assist.