Signing Error
 
 In some cases signing errors occur when using a PKCS #11 provider 
key for authentication. If your PKCS #11 provider (for example a 
hardware token) has multiple keys, it is possible that not 
all the keys can be used for authentication. 
 Try changing the Slots value in the PKCS #11 configuration 
(see Section PKCS #11  Provider).
 When experimenting with the value, saving the settings and restarting 
the application, you will see different keys being used for 
authentication. Upload the keys one at a time to the remote host computer. 
One of the keys may be valid for authentication.