I'm sure that many people have encountered this program with installing programs that were made before ME was released. At the Setup, and Error comes up saying that the operating system could be not detected, or invalid OS, or something. So here is how to fix it:

1. If it is a Single Setup File, extract it (if possible) with winzip (even if its not a .zip file).
2. Open OS.dat
3. It should look something like:
Code:
[Info]
Name=PLATFORM
Version=1.00.000

[0x0009]
OS Independent=0x0000000000000000
Windows 3.1 & 3.11=0x0000000000000001
Windows 95=0x0000000000000010
Windows 98=0x0000000000000040
Windows NT 3.51 (Intel)=0x0000000000001000
Windows NT 3.51 (Alpha)=0x0000000000002000
Windows NT 3.51 (MIPS)=0x0000000000004000
Windows NT 4.0 (Intel)=0x0000000000010000
Windows NT 4.0 (Alpha)=0x0000000000020000
Windows NT 4.0 (MIPS)=0x0000000000040000
or something similar

so what you have to do is create a ME value by adding:
Code:
Windows ME=0x0000000000000040
to the end of the file

notice that the 0x0000000000000040 number is the same as Win 98. If the program is really old, then it might have a Win 95 value, and no 98 value. Thats Ok, all you have to do it write Windows ME= and the number of the most recent Operating System Listed

I just had some spare time and though I should post this.

BTW I figured it out my self

hope this helps someone