Formatting a write-protected CD/DVD in Windows 7
To format a write-protected CD/DVD in Windows 7, you can follow these steps:

Determine write protection
- Check if the CD/DVD is truly write-protected by attempting to copy a file onto it.
- If you receive an error message stating that the disk is write-protected, proceed with the following steps.

Change registry settings
- Press the Windows key + R to open the Run dialog box.
- Type "regedit" and press Enter to open the Registry Editor.
- Navigate to the following key: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\StorageDevicePolicies
- If the "WriteProtect" key exists, double-click on it and change the value data to 0.
- If the "WriteProtect" key does not exist, right-click on an empty space in the right pane, select New > DWORD (32-bit) Value, and name it "WriteProtect." Then double-click on it and change the value data to 0.

Use third-party software
- If the above method does not work, you can try using third-party software like "HDD Low Level Format Tool" or "USB Disk Storage Format Tool" to format the write-protected CD/DVD.
- Download and install the software, then follow the instructions to format the disk.

Physical write protection switch
- Some CD/DVDs have a physical write protection switch on the case. Make sure this switch is in the "unlocked" position before attempting to format the disk.
By following these steps, you should be able to format a write-protected CD/DVD in Windows 7 successfully.