Opening Form Causes Another Desktop App To Come To The Front?

I had started a similar thread http:[url].... in May but got side tracked, tried to resurrect it by posting back to it but not getting any response so I am starting anew.I have a .net 2.0, VS2010 application. I have users that occasionaly have the following occur:

Open my application, do some work, leave it open go to another application, excel, IE, Firefox, outlook come back to my application, open a new form My application form opens but instead of it being on top with the focus some other application that was previously opened (the excel, IE, etc.) pops up the user can minimize the offending application and there is my form or go to the taskbar and select my application and there is the form

This post echos my problem: http:[url]....Although my app is a windows form app.The issue arises if I had been checking my email for example in outlook or I may have had IE open for example, so the other aplications on on the desktop not minimized. Both my app and the Outlook(the other application is not important it happens with any open application) are open on the desktop. I finish checking email, I click on my app to bring it to the foreground. I then click on a button that results in opening another form. My "I am working" form pops up. The main app now ready to display the new form closes the"I am working" form, outlook comes to the foreground and I can then see the new form in my app get displayed behind outlook.

The code flow is my app is opened, a midi child is created in the main app window.a double click on a contol causes a background worker to be started. That background worker opens a form that just shows a spinning ajax control with the words "working" in it. Meanwhile the app is busy prepping a form for display.When the form is ready to be displayed the background worker is cancelled which removes the popup form and then the newly constructed form is displayed.

At first I thought this had something to do with the background worker and a different thread being created but that is not the case.I can replace the background worker with a simple popup of a modeless dialog. Of course any work done in the background worker is not done but the modeless dialog will not block the main app. And when the main app closes the modeless dialog I get the same behavior with the last opened desktop app coming to the foreground and I can see my newly created form popup behind it.

I can of course just as soon as return from the call to close the working form give my app focus but that still results in the other desktop app coming to the foreground briefly and then my app coming to the foreground, not really a solution. With that bit of info it seems that my application is for some reason giving up focus between the time the working form is closed and the main app new form pops up.My code is way to big to post and it involves DB reads so it is just not feasible to post it.I tried recreating the scenario in a much smaller project that really did not represent much of the complexity of my application and could not get the issue reproduced.