I have both Windows XP and Windows Vista, WMP 10 and 11.\n\nI'm looking for some kind of Windows Media Plugin or codec pack that I can\npurchase that will install an ACM (Audio Compression Manager) compatible MP3\nencoder, allowing Windows Media Player and other programs to encode MP3s\nusing ACM functionality. Ideally, I would like to purchase the pack from\nMicrosoft, but third party companies would be fine as well.\n\nSome more information...\n\nWhat I get from my testing and from reading various sources online (although\nI'm not entirely sure about this), is that earlier versions of Windows Media\nPlayer (9 and earlier?) included a codec that could be used for encoding\nMP3s, While later versions, ex. WMP 11, allow only decoding.\n\nMicrosoft includes a Fraunhofer codec, and it seems that there are three\ndifferent versions of it - l3codeca.acm, l3codecp.acm, and l3codecx.acm. The\nx version is decode-only (?), and is the one enabled by default on my\ncomputers. To be able to use the other ones, it seems that one would need to\nedit the registry (which I'm not interested in doing).\n\nThere is a MS knowledge base article that states:\n\nBecause of licensing restrictions, you cannot use the L3codeca.acm file that\nis included in Windows Vista to encode MP3 content. (ID 937141)\n\nAnd another states:\n\nWindows Media Player for Windows XP has MP3 encoding plug-in support. To\nenable the Windows Media Player to encode MP3 files, you must license and\ninstall a compatible MP3 encoder. Windows Media Player supports only Audio\nCompression Manager (ACM) functions to communicate with the MP3 encoders.\nTherefore, the codec must be an ACM codec. (ID 306494)\n\nSo I guess a couple of related questions I have are:\n\n-How can I "license and install a compatible MP3 encoder"? It doesn't seem\nthat I can do that directly from Fraunhofer - their website says they don't\nsell any software.\n\n-How can I legitimately use the l3codecp.acm and l3codeca.acm codecs that\nMicrosoft includes?\n\n-What are some programs or codec packs that I can purchase from Microsoft or\nanother company, that will install an ACM compatible MP3 codec?\n\nAnother question I have is that Windows Media Player has a feature that\nallows you to rip songs from CDs to mp3, but doesn't seem to allow you to\nconvert files on your hard drive to MP3... why?\n\nAny help with this would be appreciated.