It's in the app data folder path - something like this: C:\Users\username\AppData\Local\{bunch of characters}.aplzod
type %localappdata% into the address bar of windows explorer and press Enter to jump to the AppData\Local folder.
but the easiest way to fix (and one that insures you won't have sync problems) is to sign out of iCloud and sign back in. When it asks about making a copy on your computer, say no - everything is in the cloud and you just need to restore it.