My computer is Acer Aspire V5-471G.Recently[1 Week ago] i installed windows 8 in my computer.
What i did was a clean install and not upgrade[Earlier I had windows 7 installed in it].
Being new to windows 8, i had to fix some of the issues after the install[like .NET 3.5 install,Touch pad multigesture problem etc], mainly the Wi-Fi problem 
which couldn't be turned ON but i fixed that using BIOS update to v1.22 and also fixed all the issues mentioned above.
Now there's only one problem that's bugging me and i don't know how to fix it and i had no problems
whatsoever when i had windows 7 in it.I discovered that my CD/DVD drive disappears when i resume
from sleep.And the only way to use the drive is to reboot my computer and then it's there detected
in 'My Computer'.It's like when i wake my computer from sleep it uninstalls the CD/DVD ROM driver
as it's not even listed in the Device Manager list and can't even be ejected when i push the CD-ROM
eject button.I tried everything told in the support pages---updating storage driver and all the
other drivers from acer support page and i tried to do that fix with the 'regedit' where i had to
delete 'upper filters' and 'lower filters' in the CD-ROM entry but i couldn't do that as i had no
such 'upper filters' and 'lower filters' in that entry.I tried to use the microsoft 'Fix it' tool
but that was not for windows 8 so i'm unable to fix the problem.Please help..

Try the following and see if it helps any:

 

Start > type cmd.exe then right-click on cmd.exe and, at the bottom of the screen, click on "Run as administrator".

 

Then, at the command prompt type the following ( you can copy and paste) and press "Enter":

 

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

 

Restart the computer.

Thank You for the prompt reply but it didn't work.I also had researched on this registry entry but it was not helpful.If someone else could get help from this Command Prompt line then it must be corrected as this one is not entirely correct and keeps on popping 'Error' message.The correct one is listed below although it didn't work for me,

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

If anyone has other ideas about this problem, please post and help.

Thank You.

If someone else could get help from this Command Prompt line then it must be corrected as this one is not entirely correct and keeps on popping 'Error' message.

The command I posted should be correct.

What was the 'Error' message?

Hello ashishkhanal20!

        Are you sure you installed all of the necessary drivers that belong to your particular PC from the manufacturers site? Performed all updates? If so, try installing Windows 8 on a USB drive and reboot into it and perform a 'System Refresh'. If this does not solve the issue, then save all drivers downloaded from manufacturers site and a separate removable media and reboot into USB again and perform a clean install by using the 'Remove Everything and Re-install Windows 8'  option. This should definitely solve the problem. Post back and let us know if your problem was corrected- and don't forget to vote! >_< &nbs

Mr. auggy(MVP),

I'm sorry about the previous comment as i had told that the command line you recommended wasn't entirely correct.In fact the line you wrote was entirely CORRECT and i was confused about the line previously because i mis-interpreted it from some other blog but now i cannot tell the 'Error' that used to pop in Command Prompt previously when i entered it maybe because i had forgotten to give spaces while typing the command line word by word.This time i entered your line by copying and pasting rather than typing word by word, and it said 'Operation Completed Successfully'.Then i restarted my computer and i put it back to sleep to check if it worked then i resumed the computer---Unbelievably the Drive was there,i was very happy and just to be sure that it will work fine always from now on, i again put it to sleep and resumed but this time it was gone!.

I again started looking for solutions in Microsoft support pages.Many user's problem got fixed by this line but not mine.Maybe it's because this problem of mine is associated with the condition of resuming the computer after sleep unlike theirs[They were talking about not detecting the drive in Windows 8, not the condition of sleep and resume].

In my case,it's like the computer deletes the drivers of the CD-ROM when waking from sleep.

In one of the pages[The page discussing about 'CD drive not detected in Windows 8' NOT THE DISCUSSION ABOUT CD DRIVE DISAPPEARING AFTER SLEEP AND RESUME] , one user wrote that,

" 

I have solved this issue (for now), and I was lucky in that I had two laptops, and both installed with win8. One recognised the Drive the other did not.

1) Went to the Key

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E965-E325-11CE-BFC1-08002BE10318}

The problem machine[laptop] had 0000 to 0007 folders inside this {4D3...} entry ...The good machine did not So i Deleted all but kept the folder 0000.

2) In the problem machine there was an entry for UpperFilters ... the working machine did not so i removed the UpperFilters Entry

3) Rebooted the Computer

CD drive worked

"

After reading this i went to {4D36E965-E325-11CE-BFC1-08002BE10318} and there was '0000' folder along with '0001' folder which had all the 'keys' that were inside the '0000' folder, so i deleted it as this user suggested.

I also deleted the '-atapi' subfolder that i accidentally created under the 'Services' folder when i had entered the incorrect command prompt line earlier.

I restarted the computer and went to see {4D36E965-E325-11CE-BFC1-08002BE10318} again, '0001' was back but only contained the 'Default' entry 'key' but not the keys it previously had which were also in '0000' folder.I restarted the computer and the drive was there like always.Then i put the computer to sleep, resumed back on, the drive was not there like always!.

The 'atapi' folder now contains two subfolders.'Controller0' that is created from command prompt line and 'StartOverride' that was present previously.I guessed if i could put that 'EnumDevice1' entry inside 'StartOverride',maybe the drive will appear after resuming[starting] computer from sleep, so i modified the directory in your command prompt line to make the same 'EnumDevice1' entry inside 'StartOverride'.But sadly this didn't work either.So i also deleted this 'EnumDevice1' entry from 'StartOverride'.Restarted the computer,CD drive is there again.But after sleep and resume, it disappears again!.So i've failed at every options i can think of.

Now i have absolutely no idea what to do to solve this irritating problem coz i frequently put my computer to sleep and use DVD drive often.Clean install of windows option is really not good for me as i'm not sure even that will fix my problem and i have tons of data in my computer that i can't backup in external storage.

Please help.

Thank You.

Hi SIRKEEN75,

Thank you for the reply.

Yes, I installed all the drivers from acer support page.And honestly clean install of Windows 8 is not a good option for me now as i had tons of data in my computer which were backed up in 1TB external hard drive that i borrowed from my brother before i did a clean install of Windows 8 from previously installed Windows 7 in my computer, but now the external hard drive is full of his stuffs and if i have to do a clean install now i'm going to lose all my data from C drive.Moreover the windows is new as i haven't installed unnecessary programs other than essential programs like 'Microsoft Office 13, Kaspersky Internet Security 13,Video Players, Internet browsers etc' so i don't think these programs may have done harm to the registry entry.So i can't be sure if the clean install will solve the problem for sure.

So i'll try do a 'System Refresh' but not a clean install at least not for a few weeks.

If there are other options to fix these sort of problems, please suggest.

Thank You.