We all know that writing software requires a vast assortment of skills and, above all, a lot of patience. You usually need the latter to feel comfortable when you realize that you've wasted hours and days over someone else's bug. Here's the story.
Like many commercial applications, VB Migration Partner has a splash screen. No big deal. VB Migration Partner is written in VB2005, therefore we could use VB.NET application framework. As a matter of fact, defining a splash screen in VB.NET is as easy as selecting an item in a combobox in the Application tab of the My Project designer.
During the beta test period a few users reported that at times VB Migration Partner threw an exception at launch, immediately after closing the splash screen. We never managed to reproduce the problem on our computers. Fortunately the exception occured quite rarely. Until a user running Windows 2000 reported that he was seeing the exception at nearly every launch. After installing VB Migration Partner on Windows 2000 in our lab, we could indeed verify that we had a problem.
It took a while to find out that we weren't the only ones suffering from this issue. As a matter of fact, Microsoft recognizes that it is a VB.NET bug. Fortunately, they also offer a workaround. According to whis workaround you must create an invisible form from inside the Form_Load event of your splash screen, something like this:
Private Sub Form_Load(ByVal sender As Object, ByVal e As EventArgs) _
Dim frm As New Form
frm.Opacity = 0
frm.ShowInTaskbar = False
frm.FormBorderStyle = FormBorderStyle.None
Unbelievably, this code makes the problem vanish away! You can find more details in this Microsoft KB article.
We realized that *all* applications written in VB.NET could suffer from this issue, thus we added a method to our support library, named SplashScreenBugFix6, which creates the invisible form for you. You just need to add an InsertStatement pragma in the original VB6 splash screen form, so that a call to this method is automatically generated anytime you convert the VB6 project:
' in the VB6 project
Private Sub Form_Load()
'## InsertStatement SplashScreenBugFix6()
' more code in the Load event