Hello Roger Schneider,
The error seems to be thrown from a custom user control called DepartmentMenuControl.ascx.cs
. However, the problem is that the web application cannot find Telerik.Framework.dll. Please make sure that this assemble is located in your bin and your project has reference to it. Make sure that the bin folder and this assemble are acessible form ASP.NET account. Also check whether you are not replaced the dll with another one that has version.
As I see it the control you use is looking for Telerik.Framework, Version=3.7.1990.2,
but Sitefinity 3.7 2022 build comes with Telerik.Framework version 3.7 2022
. So most probably your control has an old reference.
the Telerik team