Registering mozctlx.dll failed

I'm tr开发者_Python百科ying to install Mozilla ActiveX Control v1.7.12. In the folder where the DLL resides I execute

regsvr32 mozctlx.dll

but this fails. I get an error message

DllRegisterServer in mozctlx.dll failed  
Return code was: 0x8002801c  

I already tried an other version of the DLL, but no avail. Any ideas?

TIA

Steven

---

Run command prompt as administrator, then execute the same command.