You don't need any special controls. See http://www.craigberntson.com/Articles/kb003.htm

>I'm looking to change my application license to be based on number of users. For that reason, I need to monitor number of users of my app and prevent too many users from using it.
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>The data is currently stored in VFP but will be optional for using SQL/Access/Paradox/Firebird/etc. The front-end is currently in VFP but will be changed to VB/ASP. So I will need this to work in any language which is why I am looking to ActiveX for this.
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>Does anybody know of any controls that can restrict the number of users to an application?
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>TIA,