The easiest way to fix it is to close Android Studio (to avoid removing problems) and delete this directory:
C:\Users\<username>\.gradle
Then open your AS 1.5 and try to rebuild your project.
NOTE: .gradle
may be a hidden folder. If true, follow these steps:
To enable the viewing of hidden and protected system files in Windows
7 please follow these steps:
- Close all programs so that you are at your desktop.
- Click on the Start button.
- This is the small round button () in the lower left corner of your screen that has a Windows flag on it.
- Click on the Control Panel menu option.
- Click on the Appearance and Personalization link.
- Now click on the Show hidden files and folders option.
Under the Hidden files and folders section select the radio button labeled Show hidden files, folders, and drives.
- Remove the checkmark from the checkbox labeled Hide extensions for known file types.
- Remove the checkmark from the checkbox labeled Hide protected operating system files (Recommended).
- Press the Apply button and then the OK button. You will now be at your desktop and Windows 7 will be configured to show all hidden
files.
From: http://www.bleepingcomputer.com/tutorials/show-hidden-files-in-windows-7/