I-Cloud not opening in Windows 10

i downloaded i-Cloud in my windows 10 and i did the upload and the downloads i want from it.Then i closed i-Cloud. Later i tried to open but a popup came saying "An error occurred during authentication". So i reinstalled i-Cloud and hence it started working when i opened it directly after the re-installation but when i close the app and try to open it again,it shows the same error message. It seems like i have to keep reinstalling this i-Cloud app after every single use of it. Please give me a proper and a best solution to it.