I bought Oblivion GOTY Edition about 2 years ago from my brother's friend. The game is definitely legit - comes with the box, manual, map and DVDs. Right now I'm trying to install the game (using Windows XP Service Pack 3), but when I click on setup.exe or Oblivionlauncher.exe, my cursor changes to the mouse arrow with a disc-spinning cursor. Then, I get two error messages: 1) either it says something like "No disc detected" or something like that, or 2) it says "Please use an original disc instead of a backup", something along those lines.
I cannot, for the life of me, figure out how to get this working. Even trying to install it in Safe Mode doesn't work. But, I have a hunch it has something to with administrative rights. The first time I popped the DVD into my PC, I was prompted on which user account I want to run the program with. I was given two options: first one was the default account with my username which I've been using all along, and the second option lets me choose between Administrator or my default account. I selected the first option because the second option required a password, regardless of which account I selected. Funny thing is, I believe I only have one default account; even when I log out, I am only given the choice to select one account, and that is the one with my username, not Administrator.
(sorry if above sounds confusing, I'll post a screenshot if I can, but I am unable to replicate that window anymore)
Any ideas on how to even start setup? I've been messing with this for hours and it still doesn't work.

Do you have a SATA DVD-Rom drive ? Some older version of TAGES or Securom have some trouves with SATA drive.
But the weird thing is that you have problem with the install, on my Oblivion version had the securom check was when you tried to launch the game not when you try to install it... but maybe it is different with GOTY edition.
One solution, I know it sounds weird but often it works with similar case, would be to make an ISO of the DVD, mount it with Alcohol or Deamon Tools and then retry to install it.
I had a similar problem with Witcher (before they patch out the CD-check), my original was detected as a pirated disk while a mounted ISO was detected as being an original :-)

I had the same issue. Since the secuROM is only tied to the installer the way around it is to image your retail disks using alcohol 120% and then install using the images mounted in daemon-tools. I think remember having a tweak a setting for disk 2 other than the default profile for secuROM but I'm not 100% positive on that. And after you install you can use a "mini image" (they're only like usually 50MB ish) to mount in daemon-tools instead of having to keep disk in drive. I prefer mini images to "fixed executables" for a more pure environment that tends to be less buggy.

Thanks, I might try creating an ISO as a last resort. I'm using an IDE DVD-Rom drive. Sigh.
Ok I have a screenshot of the administrative privileges window, attached to this post

What I did with mine was install it while capturing the registry settings. I then just archived the game folder along with the reg settings for future installs. Then all you have to do is extract the game in the same place it was originally installed and import the reg settings and it works fine that way as well. Or you can just archive those alcohol images you made for future installs with daemon-tools.

Alcohol 52 doesn't work, it just can't bypass SecuROM. I'd like to try Daemon Tools, but I have no intention of buying additional software just for this. Anybody using the lite version, and if so, does it work well with emulating DRM like SecuROM?
When I load the .mds with Alcohol, and try to boot it up on E:\ (which is my virtual drive), I get this (screenshot attached)

I didn't try it with alcohol free version but I can confirm it works with full version alcohol 120%. I still wanna say I had to tweak it a little from the default securom profile but I'm sure you could find the settings needed searching google. I still have my images but I lost the intstructions I made for myself for imaging them in a hard drive crash last year. otherwise I'd tell you the exact settings used. I do remember it being relatively easy to image them though.
I can confirm Daemon-tools lite free version works fine and does the needed protection emulation.
Just to clarify - Properly imaged disks will work fine in daemon-tools free version and don't require you to use alcohol's virtual drive.

Well there is one way you could fix it...

Try a new CD/DVD drive.
I ran into the same problem when I tried to install Fable. It was only reading half the disk so it would give me a similar error.

Try TES: Daggerfall

DOWNLOAD A FUCKING CRACK.
There. It's not so hard to say. And I fucking approve. If you have bought the game, and the DRM makes it so that you can't play it, then I personally think that you are morably obliged to download a crack, in order to compensate for the developers fuck up.

Sometimes disc checks categorically won't work with your computer for whatever reason. If their presence is the problem then the solution is only found in their absence.

Or you could just say it like that. I would normally, but this is a game retail site, no matter how DRM free it is.

And why wouldn't you agree with him being able to play a game he bought and paid for? Is there any reason you wouldn't? Even Ubifail with their Big Brother DRM distribute cracks to their customers to solve these kinds of problems.

Try doing the DLA disable as recommended by SecuRom -
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A possible cause might be a CD/DVD burning software (e.g. Sonic DLA, Stomp RecordNow Max, ™) which uses the DLA (drive letter access) technology. You can disable DLA following these steps:
Click Windows™ 'Start' and select 'Run'
Type 'cmd' to get the command prompt and hit Enter/OK
Type 'dla disable e:' where 'e:' is the drive's assigned letter
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Also,I believe SecuRom will block installs if you have Daemon Tools or Alcohol xxx% installed or disk mounting software depending on the version. Uninstalling these programs may allow you continue with the install.
Also, with the install disc in the drive, right click My computer, click Manage, click Device Manager, click DVD/CD-ROM Drives, right click your DVD drive, click Properties, click the Volumes tab, click the Populate button then try to install. Might try this first as it is easiest . . . =)
Edit: All of the above is assuming you are an admin. Go to Control Panel, User Accounts and see if your current account is an admin. If not, log into an account that is an admin account. Not being an admin is usually the reason for the prompt to install as another user.