Your signature device does not support the required hashing algorithm SHA256
Here is devices/software version involved.
Mac: 10.12.6 (test in 10.13)
Adobe Acrobat: 2018.11.20058
PIV card reader:Identive Cloud 2700R, Driver:v5.0.38
Windows: 10
Adobe Acrobat: 2018.11.20040
PIV card reader: Identive Cloud 2700R, Driver:v1.09.00.02
When I tried the digitally sign, I only get the warning of "not support SHA256" on the Mac side but not on Windows' side. Both machine has latest driver of the card reader. Is there any thing I need to change on a mac machine to make it work?