iCloud Photo Stream stops working on Windows 8.1

Here's a fix for when iCloud Photo Stream stops working on Windows 8.1:

1) Kill these processes if any of them are running:

ApplePhotoStreams.exe
ApplePhotoStreamDownloader.exe
APSDaemon.exe
iCloudServices.exe
iCloud.exe

2) Delete this folder:

%AppData%\Apple Computer\MediaStream

3) Launch iCloud Control Panel. Select the Photos checkbox, and click Apply.

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