This is the error message I encountered

Error:Execution failed for task ':app:buildInfoDebugLoader'.
> Exception while doing past iteration backup : Source F:\workspace\ApplicationTest\app\build\intermediates\builds\debug\31511899501846\classes.dex and destination F:\workspace\ApplicationTest\app\build\intermediates\builds\debug\31511899501846\classes.dex must be different

This is because there is a file named classes.dex conflict under the build, you can find the specified file and delete it and run it again.
For my exception information, find the file as shown in the figure below, and right-click to delete it.