引用：http://stackoverflow.com/questions/37643239/errorexecution-failed-for-task-appclean
解决
Finally i find the solution. If you are using Android Studio 2.0 Beta, this issue might appear (more likely if you are working on NTFS filesystem) and it seems like the "Instant Run" is the culprit. Search for "Instant Run" in settings and uncheck the box. – Zacharia Mwalwama Jun 5 at 15:07
搜索命令：Instant Run(后面带有设置的那个)->取消Enable Instant Run to hot swap ...(第一个那个的钩取消掉)