Visual Studio 2003 included Visual J#. This is now completely deprecated and can often cause installation errors on 64-bit systems. If you don't need it, uncheck it during a custom installation.
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: Some users report that to avoid "Source file not found" errors during installation from ISO images, it is best to extract all discs into a single directory before running Compatibility Mode Visual Studio 2003 included Visual J#
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VisualStudio\7.1\Registration visual studio 2003 product key