DLL-files.com - mscoree.dll, free download
PRB: "Mscoree.dll Could Not Be Found" Error Message When You Try to Run a .NET Executable File
But look here too:
Cannot Access a Necessary File, mscoree.dll
"This message can be safely ignored. However, if you do not want the message to appear, you must download and install the .NET Framework. As a forewarning, the .NET Framework is fairly large, approximately 20 MB."