Fix to CD-DVD not recognized (explained)

I just fixed my W7 laptop so that it now recognizes my built in CD-DVD drive properly by manually changing the registry by adding:

1. Controller0 to atapi here: HKLM\System\CurrentControlSet\Services\atapi\Controller0
2. EnumDevice1 = 1 to Controller0

The procedure described: https://support.microsoft.com/en-us/kb/314060 and in many threads online.

Presumably the change tells the OS what ATAPI channel the CD-DVD drive uses or am I wrong? Maybe someone can explain in simple terms exactly what this fix does. Thanks.

As a besides the same fix can be done (I haven't tried this) from the CMD window by executing the below:

reg.exe add "HKLM\System\CurrentControlSet\Services\atapi\Controller0" /f /v EnumDevice1 /t REG_DWORD /d 0x00000001

Thanks.

...if you've already fixed it, what more can we tell you?

Well, you could answer my query and explain in simple terms exactly what this (Controller0) fix does. Or, if this is above your pay level, perhaps someone else can.

Your suggestion to delete the "LowerFilters" and "UpperFilters" is covered in that same KB314060 article. In my case of no relevance as I had neither/nor. But, good that this works for you (by script or manually).

Thanks mate...