have already applied device change, cable change , Android studio restarting , System restarting , adb restart and killing etc nothing helped One of my log file in sdk tools folder gives this output:
!ENTRY org.eclipse.osgi 4 0 2015-09-10 00:38:33.745 !MESSAGE Application error !STACK 1 java.io.IOException: The folder "C:\Users\Mehran%20khan.android\monitor-workspace.metadata" is read-only. at org.eclipse.core.runtime.internal.adaptor.BasicLocation.lock(BasicLocation.java:206) at org.eclipse.core.runtime.internal.adaptor.BasicLocation.set(BasicLocation.java:164) at org.eclipse.core.runtime.internal.adaptor.BasicLocation.set(BasicLocation.java:137) at com.android.ide.eclipse.monitor.MonitorApplication.start(MonitorApplication.java:53) at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:110) at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:79) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:353) at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:180) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:497) at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:629) at org.eclipse.equinox.launcher.Main.basicRun(Main.java:584) at org.eclipse.equinox.launcher.Main.run(Main.java:1438)
the log file shows eclipse problems every where while i have not installed eclipse at all.