rthdcpl.exe – Illegal System DLL Relocation. The system DLL user32.dll was relocated in memory. The application will not run properly. The relocation occurred because the DLL C:WindowsSystem32Hhctrl.ocx occupied an address range reserved for Windows system DLLs. The vendor supplying the DLL should be contacted for a new DLL.

That is the complete error message that you may get after the Microsoft’s ani-patch update is installed on your computer.

Here’s how to solve this problem

On April 3, 2007, Microsoft has released a new patch that needs to be installed to fix this problem. Go to the download page for the rthdcpl.exe patch (this will open in a new window). On the patch download page, click the “download” button and next click “run” to start the installation immediately. You can also choose to save the patch on your hard drive for installation at a later time.

Once the patch is installed, you will probably need to restart your computer to complete the installation. That’s all you need to do to get rid of the error.

rthdcpl.exe error background information

In December 2006, Microsoft was notified of a security flaw in their operating system by security vendor Determina. This so-called .ani flaw can be used by hackers to exploit Windows computers. Not only Windows XP computers, but also Windows Vista and earlier versions of Windows are vulnerable.

In April 2007, attacks of this particular flaw have become so widespread that Microsoft was forced to release a fix (patch) for this vulnerability ahead of schedule.

This vulnerability patch, that is downloaded and installed automatically through the automatic update functionality of the Windows operating system, is known to cause trouble on some computer systems that have a Realtek sound card on board.

Many computers have their sound card integrated in the motherboard, so it may not always be obvious if your computer has a Realtek sound card on board or not.

Anyway, if you come across the rthdcpl.exe error during the startup phase of your computer, just go ahead and download and install the Microsoft patch that is mentioned in the beginning of this article and you will never see the rthdcpl error again.

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