Dll Register (regsvr32) problem on Vista

I have a video capture activex dll NCTVideoDxCapture.dll. It can be easily register on windows xp or earlier versions using regsvr32 [login to view URL] but when I try to register it on Windows Vista Home Premium edition it throws access denied errors and a message window appear saying that regsvr32 has encountered problem and need to be closed. Interesting thing is that that I have a year old Inno installer which can successfully register this dll. But when I create a new inno setup with with dll then it give the same problem that i get with manual registration. I have extracted old installer and verified that the dll file is same. I am hoping that someone can help me out here. I can provide you the old installer which can register this dll successfully. ## Deliverables I have a video capture activex dll NCTVideoDxCapture.dll. It can be easily register on windows xp or earlier versions using regsvr32 [login to view URL] but when I try to register it on Windows Vista Home Premium edition it throws access denied errors and a message window appear saying that regsvr32 has encountered problem and need to be closed. Interesting thing is that that I have a year old Inno installer which can successfully register this dll. But when I create a new inno setup with with dll then it give the same problem that i get with manual registration. I have extracted old installer and verified that the dll file is same. I am hoping that someone can help me out here. I can provide you the old installer which can register this dll successfully. Please find the dll in subject attached in attachments.