Try use administrator,
在下列資料夾,右鍵->內容->安全性->編輯-> Users (改為"完全控制")
C:\Program Files\iTunes
C:\Program Files\Common Files\Apple
C:\Program Files (x86)\Common Files\Apple
C:\Program Files (x86)\Apple Software Update
C:\ProgramData\Apple
C:\ProgramData\Apple Computer
試看看囉~