In some cases after downloading the file xsim2089bbeta.zip or xsim21013bbeta.zip it is possible that your virus scanner notifies you about Trojan.Win32.Invader or similar. Mostly you get that message at the heuristic checking of the files.
This is a false error!
The suspicious code elements are the ones which are responsible for finding memory values in x-sim and they are recognized sometimes as bad virus code by the scanner software.

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