A new session could not be created. (Original error: Command failed: )

Dear all,
I am newbie
I am following tutorials and standing at Run Appium Android Automation Test In Emulator

I face a lot of issues. Currently, error just shows “A new session could not be created. (Original error: Command failed: )” not provide which command failed or something likes that. I also try to find/apply almost solution on the same error on internet, but still failed with me. Please help me.


My code:

package Demo.MyEmotiv;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.concurrent.TimeUnit;
import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.remote.CapabilityType;
import org.openqa.selenium.remote.DesiredCapabilities;
import org.openqa.selenium.remote.RemoteWebDriver;
import org.testng.annotations.AfterTest;
import org.testng.annotations.BeforeTest;
import org.testng.annotations.Test;

public class SignUpSuccessfully {
WebDriver driver;
@BeforeTest
public void setUp() throws MalformedURLException {

  DesiredCapabilities capabilities = new DesiredCapabilities();

  capabilities.setCapability("deviceName", "HT4CFJT00362");	
  capabilities.setCapability(CapabilityType.BROWSER_NAME, "Android");
  capabilities.setCapability(CapabilityType.VERSION, "7.1.1");
  capabilities.setCapability("platformName", "Android");
  capabilities.setCapability("appPackage", "CalculatorGooglePrebuilt");
  capabilities.setCapability("appActivity", "com.android.calculator2.CalculatorGoogle");
  driver.manage().timeouts().implicitlyWait(15, TimeUnit.SECONDS); 
  
 }                 
 @Test
 public void Sum() {
	 
  driver.findElements(By.xpath("//android.widget.Button")).get(0).click();
  driver.findElement(By.name("2")).click();
  driver.findElement(By.name("+")).click();
  driver.findElement(By.name("5")).click();
  driver.findElement(By.name("=")).click();
  String result = driver.findElement(By.className("android.widget.EditText")).getText();
  System.out.println("Number sum result is : " + result);
 }
@AfterTest
 public void End() {
  driver.quit();
 }

}


The console log:

org.openqa.selenium.SessionNotCreatedException: A new session could not be created. (Original error: Command failed: ) (WARNING: The server did not provide any stacktrace information)
Command duration or timeout: 10.82 seconds
Build info: version: ‘2.47.1’, revision: ‘unknown’, time: ‘2015-07-30 11:02:44’
System info: host: ‘tanpv’, ip: ‘192.168.1.61’, os.name: ‘Windows 8.1’, os.arch: ‘amd64’, os.version: ‘6.3’, java.version: ‘1.8.0_111’
Driver info: org.openqa.selenium.remote.RemoteWebDriver


Appium log:

info: [debug] Cleaning up android objects
info: [debug] Cleaning up appium session
info: [debug] Error: Command failed:
at ChildProcess.exithandler (child_process.js:637:15)
at ChildProcess.EventEmitter.emit (events.js:98:17)
at maybeClose (child_process.js:743:16)
at Process.ChildProcess._handle.onexit (child_process.js:810:5)
info: [debug] Responding to client with error: {“status”:33,“value”:{“message”:“A new session could not be created. (Original error: Command failed: )”,“killed”:false,“code”:1,“signal”:null,“origValue”:"Command failed: "},“sessionId”:null}
info: ← POST /wd/hub/session 500 10690.146 ms - 192
info: [debug] Logcat terminated with code 0, signal null

how you started Appium server before run your test? manually?