- 1). Charge your Zune battery to full. Back up your media files into a separate file on your computer. Songs that you've purchased from the Zune marketplace may be lost during this downgrade.
- 2). Uninstall the software of Zune 3.0 from your computer and reboot your computer when you are prompted to do so.
- 3). Use Windows Explorer to visit the folder C:\Windows\Inf. Click on "View" and then "Details." Right-click in your folder and change the Arrange Icons By setting to "Modified/Date Modified."
- 4). Delete the files named "oemxx.info" (each x will be a unique number) that were created on September 3, 2008, 12:29 AM. The sizes of these files will be 11.3 KB and 8.69 KB. If you wish to back up your process, rename these files and copy them into another folder.
- 5). Download and install Zune 2.5 software (see Resources). Run the software. When it asks you if you want to install the latest update choose "No."
- 6). Reset your Zune by holding "Up" (on the directional pad) and "Back." As it's restarting, hold down "Back," "Play/Pause" and the Center directional pad button. This will remove the Zune 3.0 firmware.
- 7). Connect your Zune to your computer when it prompts you to do so. Your software will show the term "Device Recovery Mode," and it will prompt you to install the Zune 2.5 firmware on your Zune.
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