WPF Validation Error Disappearing when Switch between visual items

Typical daily trials of a Software Engineer – getting WPF error validation working can be a bit of a pain, it’s a bit buggy.

I hit a problem today whereby errors marked for text boxes on a tab would disappear if you moved away from the tab and then back again, it turned out to be a common WPF problem and this post provided a fix, you just need to wrap your tab content inside an:

<AdornerDecorator>...</AdornerDecorator>

element. Bit of a pain but at least it seemed to work once I put these elements in!