Troubleshooting 'Class not registered' Error

Accessing properties of ActiveX controls via designer is a very basic feature which enable us to to implement operations like styling etc. directly at design time. However, at times, when we try to access the property pages of the ActiveX control, we get an error like “Class not registered. Looking for object with CLSID:{808A9BF8-DFA8-4A0A-BB85-F6F989EE8FDC}” error. This blog summarizes easy to implement steps to fix this issue. In order to resolve this error, search this CLSID in the registry details.

1. Start > run > regedit (Opens the registry editor).
2. Use CTRL+F to seearch this CLSID (For e.g "808A9BF8" as in this case)
3. Look for the corresponding file name ocx/dll under this CLSID.
4. Re-register that ocx/dll using regsvr32.
5. Close the Project andopen again to verify if the issue persists.

Scenario If the problem is with C1Sizer control then look for the C1SizerPpg.dll in System32 and register it Start > run > regsvr32 C1SizerPpg.dll If its Win 7 64 bit then

1. Open command prompt as Admin
2. Goto SysWow64
3. regsvr32 C1SizerPpg.dll (Make sure this is present in the dir)

This should resolve this error and you should be able to access the properties of the control.