Guide: Installing MSN Messenger 7.5 in Windows 2000
Download the exe installer file for MSN Messenger 7.5.
Open the file in a programme such as Winrar and extract MsnMsgs.msi file.
Start up your favourite Hex editor and change the value below:
Offset: 155C0
Original: 31
Patched: 30
Then save the file. You will now be able to install this on windows 2000.
that's how ahmad done it and i'm sure it's possible for other os' too just need to change some things and have that os to test it