The signature pad display stays black

My pad's front LED...

• ...stays permanently red
• ...alternates between red and green light
• ...flashes very fast in green
• ...flashes slowly in red
• ...is not showing any light at all

The signature device is not found by the used software

• My computer is running Windows 7
• I am using the signature device via TCP
• I am using the signature device via Citrix
• I am using the signature device in a virtual machine (VM)
• I might not have the most recent software installed on my system
• None of the other circumstances apply

I don't see my signature on the pad display when signing

• I am using a natura Sign Pad Classic/Biometric/Standard 2.5