FastClose Server, the Worker Service for scheduler, the Gateway Service for Acumatica, and the Reader web server have an updated pre-requisite: the ASP.NET Core Runtime 8.0.x Windows Hosting Bundle. You can find the latest patch release for it here: Download .NET 8.0.

If you have a Worker Service running for the Scheduler product, it needs to be re-registered with the FastClose Server.
Planning databases need to be upgraded once the FastClose Server has been updated. Visit the Connections page in the Admin web app and click each Upgrade button.
If you use a centralized desktop management solution such as Microsoft Intune, please note that new client installs default to installing per-user, under the Roaming AppData folder (C:\Users\<username>\AppData\Roaming). You can configure your deployment to continue using per-machine (installing to the Program Files folder). See: Per-Machine versus Per-User Installs.