Error: cyclic redundancy verification (installing Ambitions)

[Frey]

Need help again... 

Ever since installing Pets a while ago my game has been a real pain in my behind. It started crashing after 5 minutes of gameplay, so I changed the DEP settings, which didn't help much, and did a factory reset, which seemed to fix the problem... until yesterday, when it started crashing again. I did another factory reset, but it didn't work, so I got tired of the whole thing and uninstalled the game to do a full reinstall. I installed the base game and World Adventures successfully, but now I'm trying to install Ambitions and I'm getting this weird error:

"File: E:\Caches\Twinbrook.objectCache
Error: data error (cyclic redundancy verification)

Try Again - Cancel" [or something like that - my windows is in spanish  ]

So I click on try again but the error comes back, and if I click on cancel the installshield shuts down. Anyone knows what this is and/or how to fix it? My disks are obviously original and Ambition's CD doesn't look damaged  so I have no idea what this means.

I remember after installing World Adventures I had another major issue and what I did was to clean everything sims-related from my computer's registry and then install everything again... but I don't remember how I did it or where I found the instructions. Maybe that's what I should do? Does anyone know how to do it? Please help 

[Seabody]

A Cyclic Redundancy Check (I'm assuming that's what it is, since Verification and Check are synonymous) occurs when a disc is scratched. Do you hear a weird noise before the popup comes up, coming from your computer?
Now, the Cyclic Redundancy Check simply means your disc needs to be cleaned, either because of dirt or scratching. If the scratch is large, your best bet is to get the whole thing resurfaced. It should be able to be done at a video rental store, for a small fee.
Now, someone else had this problem and used another workaround, but I don't know where the thread is.

Hope this helps!

[Frey]

  You're right! the CD didn't look scratched at first but looking closer it has a MAJOR scratch all along... it's not too deep I think, but it's huge. I have no idea how it got there since the CD has been inside its original box all the time though  . I read somewhere that washing them with mild liquid soap and warm water can help so I just did that... I also read other ways to fix it like waxing it and rubbing it with toothpaste... but I'm kind of scared of doing that hehe. I doubt I can find someone to resurface it in Chile though, but I will ask around when I go to the city if washing it doesn't help.

Thanks Seabody!