Question: Every time I boot into OSX or Windows, Steam automatically starts.

Is there a way to stop Steam starting whenever I boot up my computer?

Answer: 
An alternative solution on Windows (starting from 8) is to open task manager and disable Steam Client Bootstrapper from the Start-up tab.

![Task Manager, Start-up, Steam Client Bootstrapper, Dropdown menu, Disable](https://i.stack.imgur.com/89m5b.png)

**Note:** This is an override switch to Steam's setting. You cannot re-enable it from Steam settings after disabling it here.
In Windows 7 click the Start menu and type `msconfig` in the Search box. In the System Configuration program that opens, click the Startup tab, and then uncheck Steam. This does pretty much same thing as the Windows 8 tip.