OpenFileDialog/c# slow on any file. better solution?

Question

I am opening a file using the OpenFileDialog in c# and I am noticing it is taking between 20-40 seconds to load my file and clear the dialog.

Here is my sample code

Answer 1

Another option which helped in my case:

OpenFileDialog ofd = new OpenFileDialog
{
...
   AutoUpgradeEnabled = false
};

With this option, OpenFileDialog renders simpler UI, "pre-Vista" style according to MSDN article.