If your Mac starts up to a circle with a line through it - Apple

A circle with a line through it means that your startup disk contains a Mac operating system, but it's not a macOS that your Mac can use. 

Crossed out circle at boot up. Recovery n… - Apple Community

Cancel sign what does that mean - Apple Community

Mac Smart People I Know

Help me regarding issue 2106F when I trie… - Apple Community

Erased HD - Apple Community

Si su Mac comienza con un círculo con una línea que lo atraviesa

Mac Basic Startup Troubleshooting Steps - Apple Community

My iMac doesn't start and shows a blocked… - Apple Community

Mac shutting down for no reason, and unab… - Apple Community