My mp3 Doesn't play some files

Song Formats for Mp3 Players Explained, Part II
by Tha Mp3 Doctor

WMA files are special. There are two types of WMA file, and the Mp3 or digital Audio Player documentation will not always tell which of these two types the Mp3 player will recognize. Type I is a non-licensed, or non-DRM-protected WMA file. DRM stands for Digital Rights Management, and it is Microsoft’s copyright system for music files. If you have a type of Mp3 player that will only accept non-DRM protected files, the product specs for your player will NOT mention the words "DRM" or "Windows Plays ForSure" on them (unless they are using it in the negative, such as "this player does NOT support DRM encryption"). In MOST cases (there are more and more exceptions), Windows Media Player will convert songs from CD’s that you personally bought from the store into non-DRM encrypted WMA format.

The second type of WMA file is a DRM-encrypted WMA file, and there are several subtypes of these. Every DRM-encrypted file can have "play rights," "burn rights," and "transfer rights." "Play rights" mean you can play the song on your computer, "burn rights" mean you can burn the song to CD, and "transfer rights" mean you can transfer the song to your Mp3 player. Once again, not all WMA files are created equal. If you have a BASIC subscription to a music service such as Napster, you may download songs that have "play rights" – you can play them on your computer without any problem; but they may lack burn rights and transfer rights – so you cannot burn them to CD, or transfer them to your Mp3 player without incident. The solution here is to upgrade your music service to the premium, more expensive subscription that includes burn rights and transfer rights.

Then there are "fixed-term" licenses and "unlimited" licenses on WMA files. A fixed-term license will expire after so many days, months, or years; and will require you to resynchronize your songs to the music service or to your computer in order to continue playing them. This is a key reason behind songs "disappearing." Napster and Rhapsody are two examples of music services with fixed-term licenses. You must resynchronize your Mp3 player to your computer every 30 days, and you must keep you music service subscription active. If you let your subscription lapse, then the songs that were once working will no longer be playable. Once again, the only remedies are to renew your music service subscription (legal), convert those songs into a different format that the Mp3 player will recognize (possibly illegal), or to use DRM-removal software (illegal and unreliable).

One word needs to be said about burning your own personal CD’s and transferring them to the Mp3 player. CD’s naturally put song files into CDA format. Most Mp3 players do not recognize CDA format. So you will have to use Windows Media Player (easiest, IMO) or some other software to convert the CDA files into Mp3, WMA, or some other format that your Mp3 player recognizes, BEFORE you can transfer them to the Mp3 player.

Real Audio files also have an encryption system, and may not work with most Mp3 players – check your product documentation.

Audiobooks are in their own format and bring their own special problems which fall outside the scope of this article.

There are a ton of music services out there. iTunes uses AAC format. Napster, Rhapsody, Bearshare, Spiral Frog, and many others use DRM-protected WMA format nowadays. Limewire and Morpheus generally use Mp3 or non-DRM-encrypted files. Double check the formats that your player will support BEFORE choosing a music service. Conversely, if you already have a music service, choose an mp3 player that’s right for your particular service. Note: most store workers do not have the faintest idea of what I have been discussing in this article, so don’t trust their judgment – educate yourself first.

AS A GENERAL RULE OF THUMB (as always, there are exceptions), all Mp3 players recognize the Mp3 file format. The Mp3 file format is the least problematic of all the file formats. It takes up less space on your Mp3 player than most file formats – so you can load more songs onto your player than if you were using other formats. So, if you download all of your songs into Mp3 format, or tell Windows Media Player to convert your own CD’s into Mp3 format, then you will rarely go wrong.