connecting biometric device with asp.net c# wpf software

i have a zkteco multibio 700 fingerprint device which i want to connect with my asp.net c# wpf software i m using ozesh thapa code and zkemkeeper.dll but its not connecting.

its show me the error

1. refference error of zkemkeeper.dll

   for this is m add the newget pack

2. after this its show me in the dll pass its show me message device is disconnected

 

 

 

please do some help

 

thank

 

arun kumar