If you're using Windows 10 and find the 3D Viewer to be more of a nuisance than a useful tool, you're in luck. Here's how you can stop 3D Viewer from popping up and interrupting your workflow.

1. Uninstall 3D Viewer: The most straightforward way to stop 3D Viewer is to uninstall it from your system. To do this, navigate to the Start menu, then Settings > Apps > Apps & features. Search for '3D Viewer' in the list of installed apps, click on it, and select 'Uninstall.' This will remove 3D Viewer from your system entirely.

2. Disable 3D Viewer through Default Apps: Another method to prevent 3D Viewer from opening is by changing the default apps for specific file types. Go to Start > Settings > Apps > Default apps. Scroll down and click on 'Choose default apps by file type.' Look for file types associated with 3D Viewer, such as .fbx or .obj, and change the default app to something else, like a simple photo viewer or a different 3D modeling software.

3. Remove 3D Viewer from Startup: Sometimes, 3D Viewer may be set to launch at startup, causing it to open every time you boot up your computer. To stop this from happening, right-click on the Start menu and select 'Task Manager.' Go to the 'Startup' tab, locate 3D Viewer in the list of startup programs, and disable it by right-clicking and selecting 'Disable.'

By following these methods, you can effectively stop 3D Viewer from Windows 10 and avoid any unnecessary interruptions. Whether you choose to uninstall it completely, change default apps, or remove it from startup, rest assured that you have the control to customize your Windows 10 experience to suit your needs.