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Article #17242: ActiveForms not displaying in Internet Explorer

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FAQ2242D.txt   ActiveForms not displaying in Internet Explorer
Category   :ActiveX/OLE/COM/ActiveForm
Platform    :All
Product    :Delphi 3.x  

Why do ActiveX or ActiveForms sometimes not display in Internet 
Explorer?  All that shows up is the .htm page with a blank 
square with a little red X in it.  

Its likely that you selected the licensing option when you 
created the ActiveForm and you are not deploying the .LIC file 
with your .OCX file.  

Usually licensing is not used with ActiveForms/ActiveXs that 
are being used to enhance a web site because you are giving 
the control away for free.

To disable the design time licensing locate the initialization 
section in your ActiveForm's XXXImpl file and replace the second 
to last parameter of the TActiveXControlFactory.Create call to 
an empty string like so:

    '',     0);

So, when should you use Design-Time Licensing?

Your control should use design-time only when you want to sell 
the ActiveX or ActiveForm to other developers who will then sell 
their finished applications to end-users.  That is, the control 
works in a design-time environment (ie, Delphi, C++Builder, VB, 
etc.) when the LIC file is present, but it only works in a 
run-time environment (ie, the end-user application) when the 
.LIC file is not present.

If you're deploying your ActiveX over the web, then you are by 
definition deploying to end-users (as opposed to developers) 
and you should never require a design-time license.

Also, if the ActiveForm is unsigned, the Internet Explorer must 
have its "Active content security" level set to medium.  To do 
this, go to the control panel and select Internet.  Go to the 
security tab and then press the Safety Level button.  Make sure 
the level it set to medium.
NOTE: This is only advised when designing your own controls. 
Potentially rogue ActiveX controls could damage data on the 

7/16/98 4:31:28 PM

Last Modified: 01-SEP-99