Unable to add a signature using the sign pro PDF plug-in for Acrobat Reader

Unable to add a signature using the sign pro PDF plug-in for Acrobat Reader

When trying to create a signature in Acrobat Reader using the Wacom sign pro PDF plug-in an error message appears saying that the signature could not be completed.
The error occurs in acropihandler.cpp, line 404: Error creating signing certificate: CertAddCertificateContextToStore failed

This error with the Acrobat plug-in is known to occur if "Enable Protected Mode at startup" is not turned off in Acrobat Reader.
Please go to  Menu \ Preferences \ Security (Enhanced) in Acrobat Reader and ensure that the above option is not checked.
Then restart Adobe Acrobat.