To resolve this issue:You have to manually register those .dll files into the registry which were not able to register automatically. To identify whether the .dll files can be self registered or not, RIGHT-CLICK on the particular .dll file and click on the PROPERTIES option. You will see two tabs as shown in the image below.
RUN window and type "regsvr32 C:\Windows\System32\<filename>.dll and press "ENTER". Finally you will get the message that your .dll file has been registered successfully as shown below.