Working on a fairly large WPF App with about 40 modules and using Telerik library.
We've been working on that app for a few years and today, for some reason the app started crashing with
"System.AccessViolationException: 'Attempted to read or write protected memory'"
This seems to happen fairly randomly, sometimes copying a grid, opening a context menu or moving a window.
The call stack doesn't say much: (this particular stack trace was when moving a window)
[Managed to Native Transition]
WindowsBase.dll!MS.Win32.HwndSubclass.DefWndProcWrapper(System.IntPtr hwnd, int msg, System.IntPtr wParam, System.IntPtr lParam) Unknown
[Native to Managed Transition]
[Managed to Native Transition]
WindowsBase.dll!MS.Win32.HwndSubclass.SubclassWndProc(System.IntPtr hwnd, int msg, System.IntPtr wParam, System.IntPtr lParam) Unknown
[Native to Managed Transition]
[Managed to Native Transition]
WindowsBase.dll!MS.Win32.HwndSubclass.DefWndProcWrapper(System.IntPtr hwnd, int msg, System.IntPtr wParam, System.IntPtr lParam) Unknown
[Native to Managed Transition]
[Managed to Native Transition]
WindowsBase.dll!MS.Win32.HwndSubclass.SubclassWndProc(System.IntPtr hwnd, int msg, System.IntPtr wParam, System.IntPtr lParam) Unknown
[Native to Managed Transition]
[Managed to Native Transition]
WindowsBase.dll!System.Windows.Threading.Dispatcher.PushFrameImpl(System.Windows.Threading.DispatcherFrame frame) Unknown
WindowsBase.dll!System.Windows.Threading.Dispatcher.PushFrame(System.Windows.Threading.DispatcherFrame frame) Unknown
PresentationFramework.dll!System.Windows.Application.RunDispatcher(object ignore) Unknown
PresentationFramework.dll!System.Windows.Application.RunInternal(System.Windows.Window window) Unknown
PresentationFramework.dll!System.Windows.Application.Run(System.Windows.Window window) Unknown
PresentationFramework.dll!System.Windows.Application.Run() Unknown
Avalon.exe!Avalon.App.Main() Line 52 C#
The crashing reason seems very random but always UI interaction related.
It seems something is corrupting the memory, however, there are no unmanaged code.
How to debug such problem, where to start?