I never copied Windows Media Player, since it already is included in Windows on the new PC. And usually I reinstall any program from the original disk (if compatible with Windows 7 and I still need it) or the most recent version that can be downloaded (if I still need it).
Copying a program (that is, the folder in Program Files) only is needed if you don't have a disk, you can't download the latest version and you forgot to backup the original setup program. And then success isn't guaranteed at all (it works in less than half of the cases, even if the program would be compatible if you had the original setup program).
Kees
My HP uses Window 7. I transfer my programs and files from one (Acer) to the other(HP) by a tranfer program. I don't know if it is because Windows dropped XP but I am starting to have trouble with a lot of my programs like my DVD reader/writer, Window Media Player. Does anybody have a solutions?

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