Application Lost Focus when launch through Windows Explorer

Hi all,

I am working on an MDI application using VB.NET. Applications launches
normally either from Program Files or Desktop shortcut but some times
when it launches from Windows Explorer by going Program Files >
Application Folder > click Application Exe file, application lost
focus , minimized and starts flashes as windows caption.

I did use ParentForm.Activate() method to make application active but
no success.

Is there some other way to make application active as it is very hard
to find the issue as it was not happening regularly?

Thanks

Asif