DragDrop registration did not succeed

Question

System.InvalidOperationException: DragDrop registration did not succeed. ---> System.Threading.ThreadStateException:

What does this except

Answer 1

I found this error, and I see that the one that making it shown is when using another thread calling MessageBox.Show(this, ...), where this is not done initialized.

We need to remove the owner of the message box to remove the error.