I used to have only the stable version of AS installed (AS 4.0), and occasionally it wouldn't start. It would show it's loading screen, but then that's it. If I hover over the AS icon in the status bar, it shows a blank (white) screen. It will however present the 'tips' window. I had to uninstall/reinstall it, which sometimes took several tries until successful. This would fix the problem, but is not a solution.

Now I have the preview beta installed side by side (AS 4.1-beta4), and it is that version that occasionally has problems starting, and the stable version has interestingly become, well, stable.

I have my JAVA\_HOME environment variable as: C:\Program Files\Android\android-studio\jre\bin and added a second one just now just in case: C:\Program Files\Android\android-studio-preview\android-studio\jre\bin

I had a JDK\_HOME variable as well, but deleted it after I read it was redundant. It didn't change anything. I'm using Windows 10

Update:
I now notice this problem occurs only when a specific project wasn't closed properly due to the computer's battery running out or a Windows crash. Should I delete one of the folders or files in order to 'reset' the project for a clean Android Studio build?