When you open the SDK sample and try to connect the device but it is not available with error BS_SDK_ERROR_CANNOT_CONNECT_SOCKET(-103).
Case 1. BioStar 2 SW service is running.
Solution : Please turn off BioStar 2 services.
Case 2. Device can not be connected.
Case 3. Port 51211 or 51212 or 51213 is blocked or used by another program.
Solution : Add a rule for port 51211 & 51212 & 51213 in firewall setting(or turn it off) and turn off the other program using 51211 or 51212 or 51213. Check netstat -ano in command window and see if the port is used.
Case 4. Device has a certificate(SSL configuration) with other server before.
Solution : Restore to the factory default to delete certificate in the device. Do not use SSL connection if you don't need to. (Press 'N' to the ssl configuration in the first screen of sample code)
If the issue persists even after checking above cases, please collect all results of above and contact Suprema technical support team.