Step 2: Go to the Startup tab, locate Steam Client Bootstrapper, right-click it, and choose Disable from the context menu. Step 1: Open Task Manager in Windows 10/8/7. By doing this, the Steam Client Bootstrapper process will be forced to stop on startup even though you check the option mentioned in the above method. In Task Manager, you can prevent steam from opening on startup. Stop Steam from Opening on Startup via Task Manager After that, you won’t see Steam when booting into your computer unless you run it again. Step 4: Ensure the option of Run Steam when my computer starts is unchecked. Step 3: Choose Interface on the left-hand side. Step 2: Click the Steam menu in the top-left corner. Step 1: Run the Steam client on your computer that is running Windows or macOS. Thus, you can uncheck it in the Steam setting panel to stop it running when the system boots. When you install Steam on your computer, there is an option called Run Steam when my computer starts that is checked by default. Read More How to Stop Steam from Opening on Startup in PC or Mac Prevent Steam from Running via the Steam Settings