A PInvoke exception may occur when starting to edit a cell. This issue was fixed in version 0.8.5.1. To fix this problem in a development environment, follow these steps:

1. Open the ReoGrid project.

2. Open the source file Common/Win32.cs.

3. Find the definition of the SendMessage method:

   public static extern int SendMessage(IntPtr hWnd, uint Msg, long wParam, long lParam);

4. Change the last two parameter types from long to IntPtr, as shown below:

   public static extern int SendMessage(IntPtr hWnd, uint Msg, IntPtr wParam, IntPtr lParam);

5. Find the caller of the SendMessage method in ReoGridControl.cs and change the arguments to:

   new IntPtr(value)

6. Rebuild and done.