Hi!, This error occurs when you haven’t select the “module” from the drop down list at build configurations of Android Studio IDE. The module may not appear in drop down list for several reasons.

If you get this error while running an imported project to Android Studio IDE most probably the reason are:

• You may haven’t imported the project correctly. Select the “settings.gradle” file when importing existing project.
• The content of the module may be missing. This happened to me while downloading the project from Dropbox. The file structure of the project was slightly messed.

Otherwise, “syncing the gradle files” should work as usual.