Hello Larbo52
Welcome to Apple Support Community. From what I am understanding is you're having an Error when downloading an update for iCloud on PC with using Windows 7, correct? Let's take a look into this!
Ensure an anti-virus protection software is not allowing access for the iCloud update to download. Here is an article on troubleshooting iCloud for PC: Get help using iCloud for Windows
Here is an article and download of iCloud for Window 7, if re-downloading is required to the PC: Download iCloud for Windows
If the issue persists, please don't hesitate to post a reply!
Cheers!