[Solved] SpinEditor and DropDownList got Bugs in Version 2026.2.702

[Endre]

I have a WinForms-App with .NET 8

I put two Controls in the Form (nothing else, not one line of code)

 private Telerik.WinControls.UI.RadDropDownList radDropDownList1;
 private Telerik.WinControls.UI.RadSpinEditor radSpinEditor1;

The SpinEditor does not Spin, updown-buttons don't work, updown-keys don't work.

The Dropdownlist, does not dropdown when clicking on the down-arrow (it does nothing then)

but it drops down when clicking in the white textbox area.


I changed my version back to 2025.2.520, what I used before, and everything works perfect.
Something happened in this library update. It's unusable as it is now.

[Dinko | Tech Support Engineer]

Hello Endre,

The reported behavior is already fixed. The fix is included in the 2026.2.715-preview version of our controls. You can update the assemblies to their latest version. May I ask you to update the assemblies/nuget and share whether the reported behavior is still observed?

Regards,
Dinko | Tech Support Engineer
Progress Telerik

[Martin Hamilton]

what do we do.... do we just overwrite the files in the 48 folder with the preview files?

E.g. will that update the GAC

[Dinko | Tech Support Engineer]

In the first post, it was mentioned that you are using the .NET 8 version of our controls. In that case, you can update the AllControls NuGet to that version:

[Martin Hamilton]

I'm using .net 4.8

is there a particular dll or dlls that need to be overwritten such as wincontrols.dll?

and if I overwrite them will it update the GAC in the case of using .net 4.8

[Endre]

Yes thanks, it's fixed with this update.

So I just learned, using the preview is less buggy, then using your release versions.

[Martin Hamilton]

I'm having the same issue using .NET 4.8

is there a particular .dll (like WinControls.dll) that needs to be overwritten - if there are others please let me know about them as well.

and since I'm using .net 4.8 will simply overwriting the dll(s) update the GAC in this case?

[Dinko | Tech Support Engineer]

Hi Martin,

You will need to replace all assemblies referenced in your project. You can download the Preview version from your account. You can follow the steps listed in the Download Product Files. As you are using assemblies and not NuGet in your case, you can download the first ZIP file:



Then you can extract the files from the ZIP on your machine. Then you can replace all assemblies referenced in your project with the preview version that you have just downloaded. 

This approach can be used until our next official version is released. It is scheduled for mid-August. You can use the preview version so that you can continue working on your application without any errors.