Uninstall VB6 causes error message: You do not have a license to use this control
I was running out of disk space on one of my machines, so I used my TreeMap program to see where I could delete files to save space.
I saw that I still had VB6 on the machine, and I didn’t need it on that machine any more, so I uninstalled it.
It's amazing how little disk space VB6 occupied, compared to VB.Net! I remember when FoxPro came on floppy disks, and Turbo Pascal came on a single (360k ?) floppy disk!
The next year (actually only several days later <g>), I tried running my trusty picture viewer which allows me to query and show my pictures and movies to show them or thumbnails. I received an error message: "You do not have a license to use this control".
I thought that it must have been the movie player ActiveX control that was giving me the problem.
I started Visual Studio and attached to the process, and found that the error occurred when MSCOMCTL.OCX was being loaded. That triggered a memory that I had removed VB6 a while ago. I think the MSCommon controls, such as the TreeView, ListView, Slider, etc originated from VB5, and Visual FoxPro and other products repackage them.
Upon further debugging, I found that it was actually the Slider control (which allows me to slide through almost 30,000 pictures/movies) that was giving the error.
thisform.AddObject("oSlider","cSlider")
WITH thisform.oSlider
.left=350
.width = 350
.visible=1
.min=1
.borderstyle=1
.largechange=1
ENDWITH
DEFINE CLASS cSlider as olecontrol
oleclass="mscomctllib.slider.2"
PROCEDURE keypress(p1)
thisform.keypress(p1)
PROCEDURE change
thisform.txtNum.value=this.value
thisform.txtNum.valid
ENDDEFINE
I just needed to find what registry keys needed to be added back, so the application would work again. I found this link, which worked perfectly:
You receive an error message "You do not have a license to use this control" when you use Visual Basic 6.0 controls in Visual Studio 2005 or in Visual Studio .NET
see also
Microsoft Visual Basic 6.0 Common Controls