Win7: Event 7026 - boot-start or system-start driver failed to load

Problem:
After installing Windows 7 with an external DVD drive, I noticed there's a system error in event viewer:

The following boot-start or system-start driver(s) failed to load:
cdrom

I was surprised because I don't have an internal DVD drive, and my external DVD drive was no longer connected. I would not expect Windows to attempt booting from a DVD drive.


Solution:

1. Open regedit
2. Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\cdrom
3. Change the value of Start to 3 (manual) or 4 (disable)


Ref:
Event ID 7000 or 7026 is logged in the System log on a computer that is running Windows 7, Windows Vista, Windows Server 2008 R2, or Windows Server 2008
Nonexisting CDROM keeps failing to load... - Microsoft Community