Error Message "Class Not Registered" when dropping new component onto form

Question

Using Windows XP running Delphi 2010.

I have been provided with a third party package called CsdEft.ocx (for interfacing to EFTPOS terminals)

To install I did the following:

• Select "Import Component"
• Select "Import ActiveX Control"

• Select "Add" then select CsdEft.ocx. The selected OCX is displayed. Click Next.

  Shows dialog:

  Class Name: TCscEFT

  Pallet Page: ActiveX

  Unit Dir Name: C:\Delphi\Components

  Search Path: $(BDS)\lib;$(BDSUSERDIR)...................

  Generate Component Wrappers - Checked

• Click Next.
• Select "Install into New Package"
• Enter EFTPOS as the package name.

• Click Finish.

  Dialog shows:

  Package C:\Documents and Settings.............\EFTPOS1.bpl has been installed. The following component(s) have been registered: TCsdEft.

OK . All looks fine.

I can see the component in the ActiveX page in the Component Pallet.

BUT when I try to select the component and drop it on a form I get "Class Not Registered" error.

Hopefully someone can give me some pointer to what is wrong here.

Answer 1

Sounds like the OCX itself is not registered with Windows using the command-line regsvr32.exe tool. You imported the OCX file directly, so the IDE created a component wrapper based on the OCX's embedded TypeLibrary, but the wrapper is going to try to instantiate the ActiveX object via CoCreateInstance(), so you will get a "Class not registered" error if CoCreateInstance() cannot find the OCX.