Hello Pierre,

Thank you for your post!

I have been testing the sample application you have provided, but I can't seem to reproduce this behavior you are seeing. I have tried deleting the value and exiting both inputs, but when I set the value, either by usage of the spin buttons or by typing, the error message disappears on my end. My tests were made using the latest version of our 15.1 suite of WPF controls; specific version 15.1.20151.2122. The reason I ask this specifically is because I see that in the other forum thread, you reported that in version 14.2.20142.2224, this issue was fixed. Does the specific assembly version I mentioned above (15.1.20151.2122) match the ones you are using?

Please let me know if you have any other questions or concerns on this matter.