The Windows Installer kept hanging on “removing backup files”. I was also having problems installing iCloud on WIndows 10 that I have been dealing with for a long time. ICloud for Windows 10 repair and installation failures are fixed by uninstalling Outlook and all Apple related software including iTunes, iCloud for Windows, Apple software updater, Apple mobile device support, Apple’s Bonjour and (two versions of) Apple Application Support (iTunes 9 or later) with Revo Uninstaller Pro (So far the sole working solution for me). If both are present, be sure to uninstall both versions. Apple Application Support (iTunes 9 or later): On some systems, iTunes might install two versions of Apple Application Support.If it is not removed completely, the fix will not work. Based on my findings the use of Revo Uninstaller is elementary to uninstall the all Apple software really completely.Please take care of the order of the steps!.Open Outlook and wait until iCloud email, iCloud contacts, iCloud calendars and iCloud tasks are synced.Note: If you got 2-step-authentication activated you do not need an app specific password! ICloud for Windows 10_08_successful set up of iCloud with Outlook after reinstallation ICloud for Windows 10_07_set up iCloud with Outlook after reinstallation Open Revo Uninstaller Pro and uninstall completely every single Apple software program (iTunes, iCloud for Windows, Apple software updater, Apple mobile device support, Apple’s Bonjour and Apple Application Support).There’s a 30-days free trial that works, too.

Download and install Revo Uninstaller Pro.

Note: If you got an Office 365, uninstall it completely including Outlook.

Uninstall Outlook 2013 completely from your Windows PC.

Here’s how I resolved it (this tweak is not working for Outlook 2016! Update : iCloud For Windows 5.1 Supports Outlook 2016 On Windows 10): I had the same problem while repairing the iCloud for Windows 10 installation, getting the first mentioned error message. This may indicate the problem with this package.’

‘The installer has encountered an unexpected error installing this package.

If the problem persists, choose Tools > Download Only and try installing manually.’

‘Errors occurred while installing the updates.

Contact your support personnel or package vendor.’ A program run as part of the setup did not finish as expected.

‘There is a problem with this Windows Installer package.

These are common error messages of the iCloud for Windows installer: ICloud for Windows 10_02_repair in settings apps and features ICloud for Windows 10_01_repair to use iCloud with Outlook

Icloud for windows 10 64 bit