To Codemasters: the details below don't explain how to defeat the protection system on the game, nor do they provide any links to help do that, simply to remove it, in order to protect the user's PC. It's up to the user themselves to then find the required file to allow the game to work. I hope this doesn't contravene your rules, as I'm just trying to help people play all the ToCA and GRID games on their one PC (much as I do!).
This game relies on the Starforce protection system, which works fine in Windows XP and might work on Windows 7 if you install the SFUPDATE patch before running the game, which you can get from their official site here: http://www.star-force.com/support/drivers/
(find the link under "2. Versions before 5.5").
However, the early version of Starforce used will NOT work on Windows 8 (it may even prevent your system from booting) and won't work in Windows 8.1, so you'll need a workaround, as detailed below.
1. Install game from DVD-ROM (note: it takes a long time to decompress the 43 sections percentage part on Win8.1 64bit at least), then DO NOT START THE GAME.
2. If you installed the game from the autorun menu, Exit it.
3. Download and install the 1.1 patch, this can be found on the Patches Scrolls site, again DO NOT START THE GAME.
4. At this point, and if you're feeling brave AND running Windows 7, you can try the SFUPDATE mentioned above, then run the game. However if you're worried Starforce might break your PC then read on...
5. Download the Starforce removal tool from http://www.star-force.com/support/drivers/
(find the link under "2. Versions before 5.5"). Run this to ensure Starforce is removed. With any luck (i.e. you didn't run the game yet) then no Starforce drivers will be found!
6. You now need to locate a ToCA Race Driver 3 "No-CD" patch. I can't help you at this point, but searching online should help. Note: there doesn't seem to be a 1.1 version available, so you'll have to use the 1.0 version, which means some of the 1.1 patch fixes may not work. Also, please virus check whatever you download, as there's no guarantee it'll be virus free.
7. The file you download may be a replacement RD3.exe file, in which case, just copy it into the folder you installed the game into, overwriting the original.
8. Run the game's "Configure ToCA Race Driver 3" link, to set up the graphics and sound. Note: the maximum refresh rate available under "Graphic -> Advanced Settings..." might not be the highest your monitor can take. So once you've applied the settings you with, click "Save and Exit", then open the pchardwareconfig.ini file (in the "savedata" sub-folder of the game's install folder) and change the "FullScreenRefresh=" to the maximum refresh rate you wish to use (on my monitor it would only let me select 120hz in the settings, but I changed this to 144hz in the .ini file, which my monitor can take).
9. Run the game!
Note: on my graphics card (Nvidia GTX 980) there's some flickering all over the car bodies, unless reflections are turned off completely (which looks terrible too!) in the hardware settings. I think this is a driver issue, sadly, so it might be fine on an ATI card.
Also: if you select a widescreen resolution then the game will run at that resolution, but you'll lose some of the top and bottom of the image, including parts of the in-car cockpit view. So it's best to use a 4:3 resolution if you want to see the whole image, or go seek out the cam hack utility by Racer_S for more tweaks.