Hy Molly you too here
i really doubt that Gimp may dump any ddl in System or in System 32 folders..because all gimp dll in Windows are inside the Gimp folder
Basically on windows the "normal" gimp is as portable apps (because is all self-contained in the program folder, except for a space in the user directory for preferences and user add on)but with a defect..at loding time it search for dll everywhere and only when and if didn't found them in the wrong places, (=were other programs usually store them but never gimp :in "system" and" system32" ) start to search in the right place, in its own folder
But the problem is that if Gimp find the dll there, in the Windows innards, were should not be, it stop the search but instead then be happy it gives errors, (before to notice to have the right dll in the right place )
TO SOLVE
Look as suggested but if you found that dll not ONLY in Program Files/Gimp but ALSO somewhere else...you may just try to rename that in System (as example add "old_" to the dll name )
..reload gimp and see if the message is gone
--------------------------------------------------------------------------------------------------------------------
HEM...Then may remain a problem for some other apps looking for that dll...but may even be something you unistalled a lot of SW forgot dll behind when unistalled