I found out today that as of version 5.50, Winamp will no longer run on Windows 98(SE) or ME.
Winamp 5.50 installs successfully on 98/ME, but crashes when you try to run it.
Winamp 5.51 and 5.52 give a message saying that your version of Windows is 'no longer supported' when you try to install them on 98/ME.
Winamp 5.531 crashes with a Windows error message when you try to install it on 98/ME.
None of this is made clear on Winamp's download page. You have to look in the FAQ to see that the latest version now requires Windows 2000 or higher. No link is provided to download a previous version that works on 98/ME; you have to go to a third-party site like Winamp Heaven.
The last version of Winamp to run at all on 98/ME is 5.36 Beta. However, several features relating to CD playback and CD burning were broken for 98/ME users as of 5.35, so the last Winamp version to fully work on 98/ME is 5.34. Or, you can install 5.35 or 5.36 Beta and then copy over the in_cd*.dll files from 5.34.
In fact, the one good thing is that Winamp's DLL files are highly backwards-compatible, at least up through 5.3x. I have Winamp 2.95 on my 98SE computer, but I've upgraded it with the input, output, and DSP plugin DLLs from 5.35.
The Winamp developers claim that maintaining 98/ME compatibility was keeping them from implementing new features -- mostly frills that Winamp users don't want or need anyway (otherwise, wouldn't we just use Windows Media Player instead!?). The 'Full' version of 5.531 is now over a 10 MB download, compared to 1.2 MB for the 'Lite' version of 5.35!