unable to sign in to iCloud drive on iCloud for windows app

Hi Kephlin,

Thanks for contacting Apple Support Communities!

We understand that you're unable to sign into the iCloud app on Windows 10.

Do you happen to have any security software installed on your PC? If so, it can prevent iCloud from connecting with the Apple servers. You can learn more about what to look for here: Resolve issues between iCloud for Windows or iTunes and third-party security software - Apple Support

"Things to check first

Before you change your security software's setup: 

• Make sure that the date, time, and time zone are set correctly on your computer. Learn how to update these settings on a Mac or on a PC. 
• Log in to an administrative user account, not a guest account. Learn how to do this on a PC. 
• Update to the latest version of iCloud for Windows or update to the latest version of iTunes.
• Make sure that you have the latest software on your Mac or on your PC.
• Make sure that you set up Windows Hello. Learn how to set it up. 
• Make sure that you only have one type of security software installed. If you have more than one type of security software installed, you might experience performance issues."

If you're still unable to sign in, we'd suggest that you reach out to Apple directly to investigate this further with you. You can find their contact details here: Contact Apple Support 

Take care!