Everybody but the record industry agrees that the Microsoft licensing feature is awful. Luckily, you have a way to turn it off:
1. Choose Options from Media Player's Tools menu.
2. Click the Copy Music tab.
3. Remove any check mark from the box marked Protect Content.
If no check mark is there, Media Player doesn't embed any license or copy protection in your copied files. Disabling the licensing feature lets you copy your files to any of your computers and portable music devices.