Game won't download

kaidocult​  If you're downloading the game and any DLC, try downloading the base game only.  You can install the DLC separately.

If that doesn't help, try changing the location where you're installing the game.  Create a new folder on the root level of the drive of your choice, e.g. C:\Games rather than C:\Program Files\Games, and tell Steam to install Sims 4 there.  If you don't see the option when downloading, you can change the default location for your Steam library instead:

https://help.steampowered.com/en/faqs/view/4BD4-4528-6B2E-8327

If that doesn't help either, please let me know whether you're installing on an internal or external drive, and if external, the format of the drive.  You can see it by clicking Windows key-X and opening Disk Utility.

Please also provide a dxdiag.  Click Windows key-R, enter dxdiag in the run box, wait for the scan to finish, click "Save all information," and save the file to your desktop.  From there, you can attach it to a reply using the paper clip (Attachment) icon included with the other formatting buttons.