Hello and welcome to the Community, virusys.

It would be my pleasure to help you with the Intuit FCS service in QuickBooks. However, I need additional details to provide the exact troubleshooting for the issue.

We usually perform Clean Install/Uninstall to fix any QuickBooks component problem on a system. To avoid doing this, I need more information about what's happening on your end including when you run QuickBooks Desktop.

Any extra details or screenshots you can provide will help to ensure a timely solution.