Sims 4 Won't Download

These tips might help:

General Download issues

Please refer to this article for Origin and Connection issues: Origin Errors and Connection Issues FAQ

The most common Download issues are as following.

Download doesn't start 

• Most often the Firewall or Antivirus Program blocking the connection. Make sure to add Origin.com as an exception and check the quarantine if it's not blocked.
• You can also try starting Origin as administrator.
• You have Proxies turned on --> Turn them off in your Internet settings.
• Last but not least, check that no other programs interfere with Origin. Best way to do so would be running a Clean Boot.
• Reset your hosts file 

Download is really slow despite of fast Internet connection 

This is usually the case if there's lots of people downloading at the same time. You can try pausing the download and resuming to see if it picks up in speed.

Download reverts to lower percentage

Try turning on Safe Downloading in your Origin Options (click on the spoiler below to view an examplary screenshot).

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 Source: http://answers.ea.com/t5/The-Sims-4/FAQ-Serial-Codes-Game-Activation-and-Download-Issues/td-p/4228232#download