|You may try to re-register the new .dll file.|
Open a command prompt with admin rights and type in
regsvr32 <path to .dll file>
Ex: regsvr32 C:\Windows\system32\abc.dll
After this, you must get a message "file registration successful" or something to that effect. If you do not get this message, something is wrong.
I suggest you should update your DirectX files.