This is for Microsoft Windows 8 , Occurs when newly attached DVD-RW , DVD-ROM Drive or Hardisk Drive is not shown in My Computer.
Could you please try to do following and let us know if solved the problem.
1. Run Command Prompt as an Administrator.
Type cmd in Windows 8 Metro UI and press cltr+shift+enter
2. Type following and say enter
reg.exe add "HKLM\System\CurrentControlSet\Services\atapi\Controller0" /f /v EnumDevice1 /t REG_DWORD /d 0x00000001
3. Reboot the system
4. Verify if the problem has been resolved