Check this https://www.skyfiles.net/faq.html#q8
.When I open Skyfiles for the first time, why does a Google login page pop up, instead of Skyfiles asking for my email and password directly?
This is OAuth, Google’s recommended login method for all third party products. It is a much safer authentication standard, and protects your credentials from being leaked to third parties.
If you don’t get the popup, it’s due to System- or AV program- Settings.
Maybe the popup appears behind Skyfiles window
Check your Taskbar for the popup icon.