Hello all, sorry to hear about your issues with CRC checks.
For Disc based Simmers:
Something that you could try to do would be to copy the contents of the install DVD to a folder on your hard drive and install from there.
I just successfully installed Sims 3 from the DVD so I cannot attest to whether or not this will solve the issue.
If interested follow these steps:
1. First, run Windows/Microsoft Update if an internet connection is available and look for any Hardware updates that are related to your DVD drive and install them.
1. Then create a folder called something to the effect of "Sims3Install" (without quotes) on your hard drive, (e.g. C:\Sims3Install\).
2. After which, insert the Sims 3 DVD into your DVD-ROM drive.
3. Close the Autorun prompt that appears and open My Computer.
4. Navigate to your DVD Drive and select all the files/folders (you can also press the Ctrl + A keys).
5. At this point drag and drop all the files/folders into the \Sims3Install\ folder.
6. After the file copy process completes open the \Sims3Install\ folder and double-click the "Sims3Setup.exe" and attempt to install from the Hard Disk.
Hopefully this will help some with the CRC issue.
If anyone attempts this please post your results.
Best of luck and hang in there.
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|UPDATE|
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As chrissyms0 had mentioned, upon searching the thesims3.com/help site for "Cyclic Redundancy Check" EA has also included these steps as a possible work around. There steps may be easier to follow then the ones posted above.
DIRECT LINK TO SIMS 3 HELP ANSWER
Answer
This is typically caused by an error reading the disk. There are a number of steps that will help to prevent this error from occurring.
* End all unnecessary background processes. This will help insure that the installation is not conflicting with programs and processes running concurrently.
o How to end background processes
* If that does not resolve the issue, you should continue with some basic installation troubleshooting. These steps will resolve conflicts with the actual installer, itself.
o Installation troubleshooting steps
* If you still experience the issue, try CD-ROM troubleshooting to verify the integrity of the disk.
o CD-ROM troubleshooting steps
* If none of this works, you will want to attempt a hard drive installation of the game. In this process, you copy the game files to the Desktop, so that the disk, although necessary for running the game, is not necessary for installation.
1. Right-click the Desktop, select New, and select Folder.
2. Insert the Install Disk into the drive.
3. Exit any autoplay screen that may appear.
4. Open My Computer.
5. Right-click the CD-ROM drive containing the Install Disk and select Open.
6. Click Edit at the top of the window.
7. Click Select All.
8. Click Edit again.
9. Click Copy.
10. Close the window.
11. Right-click the New Folder on your desktop and select Paste. (The game files will now copy.)
12. Once the files from the Install Disk are copied proceed to step 20.

(Edited by DonJuan to remove the multiple Disc steps, since there are none as someone pointed out

)
20. Upon completion, remove all disks from any drives.
21. Double-click the Setup folder.
22. Double-click on the Sims3Setup.exe icon, looks like two silver arrows and a half-cirle on a blue background. (The installation should now begin.)