# Help To Start ReactNative **URL:** \ **Category:** Help/Discuss\ **Created:** [December 29, 2018, 4:49pm UTC](https://discuss.gradle.org/t/help-to-start-reactnative/30008 "2018-12-29T16:49:27Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![mjeimani](https://avatars.discourse-cdn.com/v4/letter/m/e5b9ba/32.png) [@mjeimani](https://discuss.gradle.org/u/mjeimani)\ **Post date:** [December 29, 2018, 4:49pm UTC](https://discuss.gradle.org/t/help-to-start-reactnative/30008/1 "2018-12-29T16:49:27Z")
Hello, Looking for some help on an issue where i get an error every time :: F:\Files\EimanMJ\ReAct\eiman\>react-native run android Unrecognized command ‘run’ Run react-native --help to see list of all available commands F:\Files\EimanMJ\ReAct\eiman\>react-native run-android Starting JS server… Building and installing the app on the device (cd android && gradlew.bat install Debug)… > Configure project :app > Observed package id ‘build-tools;28.0.2’ in inconsistent location ‘F:\Files\Eima > nMJ\app\Android\sdk\build-tools\android-9’ (Expected ‘F:\Files\EimanMJ\app\Andro > id\sdk\build-tools\28.0.2’) > Observed package id ‘platforms;android-28’ in inconsistent location ‘F:\Files\Ei > manMJ\app\Android\sdk\platforms\android-9’ (Expected ‘F:\Files\EimanMJ\app\Andro > id\sdk\platforms\android-28’) FAILURE: Build failed with an exception. - What went wrong: Execution failed for task ‘:app:installDebug’. > com.android.builder.testing.api.DeviceException: No connected devices! - Try: Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights. - Get more help at [https://help.gradle.org](https://help.gradle.org) BUILD FAILED in 2s 27 actionable tasks: 1 executed, 26 up-to-date Could not install the app on the device, read the error above for details. Make sure you have an Android emulator running or a device connected and have set up your Android development environment: > **[Introduction · React Native](https://reactnative.dev/docs/getting-started.html)** > > This helpful guide lays out the prerequisites for learning React Native, using these docs, and setting up your environment.