AME won't open: dvacore.dll?

Hi,

I have been having problems with Premiere Pro CS4 since I got it. The program itself has been fine, but I have had difficulty exporting my projects successfully. Originally, each project would fail while queued in AME, now, its worse. When I try to open AME through PPro, nothing happens. When I try to open AME seperately, I get the following error:

Adobe Media Encoder.exe - Entry Point Not Found
The procedure entry point ??0NewHandlerInitializer@ErrorManager@config@dvacore@@QAE@XZ could not be located in the dynamic library dvacore.dll

This means nothing to me, would not even know where to begin...

I have tried uninstalling and reinstalling PPro (numerous times), I have done all of the things that I have seen advised on forums, but nothing seems to work. Any help? I've got a deadline that I don't want to miss just because of this!