Problem installing itunes and three previous versions on Win 8.1 to no avail

Prior to attempting to reinstall the last 3 updates of the 64 bit version of itunes I have killed the temp folder, unistalled all of itunes and quicktime includind deleting the folders.  I have rebooted, downloaded the newest version, ran the installation as Administrator and installed the software only to get a CoreAudioToolbox.dll missing error with a second reinstall itunes error 126.  Then I came across a "fix" that if one found a copy of CoreAudioToolbox on the net and put this with the itunes.exe it would run.  So I tried that.  (I may have these slightly out of order sorry) and continued this process of adding the missing dll to the itunes folder.  At this point it seems the itunes.exe cannot find the following CoreAudioToolbox.dll, CFNetwork.dll, CoreFoundation.dll, CoreGraphics.dll, CoreMedia.dll, QuartzCore.dll, WebKit.dll, libdispatch.dll, libicuin.dll and JavaCoreScript.dll.  Now I do not know if these dlls are 32 bit or 64bit when getting them off the net so that is another area where things could go bad but at least I can see a pattern of numerous dlls that itunes.exe can't find.  Normally these dlls would be located in the sys folder i believe so something in the installation has misdirected the exe file so it cannot find the proper dlls or it has corrupted a whole string of dlls listed above which seems unlikely.  Can someone help me get my itunes running.  Its been down several months now and my wife and I both use itunes for our iPhones and iPad so a catastrophic failure of the software is fatal at many levels.  Thanks

Try Andrei Cerbu's post here or see TS1538: iOS: Device not recognized in iTunes for Windows, in particular section 5, forcing a driver update.