ERROR: Exception on thread Thread[main,5,main]

[wakedak]

C:\Users\admin\Desktop\test\platform-tools>adb devices

8b2a98ae        device

C:\Users\admin\Desktop\test\platform-tools>adb forward tcp:27185 localabstract:scrcpy

27185

C:\Users\admin\Desktop\test\platform-tools>adb shell chmod 755 /data/local/tmp/scrcpy-server.jar

chmod 755 success

C:\Users\admin\Desktop\test\platform-tools>adb shell CLASSPATH=/data/local/tmp/scrcpy-server.jar app_process / com.genymobile.scrcpy.Server 2.1

[server] INFO: Device: [OPPO] OPPO OPPO R9s Plus (Android 6.0.1)
[server] ERROR: Exception on thread Thread[main,5,main]
java.io.IOException: Connection refused
        at android.net.LocalSocketImpl.connectLocal(Native Method)
        at android.net.LocalSocketImpl.connect(LocalSocketImpl.java:290)
        at android.net.LocalSocket.connect(LocalSocket.java:130)
        at com.genymobile.scrcpy.DesktopConnection.connect(DesktopConnection.java:50)
        at com.genymobile.scrcpy.DesktopConnection.open(DesktopConnection.java:100)
        at com.genymobile.scrcpy.Server.scrcpy(Server.java:106)
        at com.genymobile.scrcpy.Server.main(Server.java:199)
        at com.android.internal.os.RuntimeInit.nativeFinishInit(Native Method)
        at com.android.internal.os.RuntimeInit.main(RuntimeInit.java:354)

ERROR: Exception on thread Thread[main,5,main]
java.io.IOException: Connection refused

How to handle it?