With it, the command runs without further prompting. Only trial and error helps you determine which are required and which are optional. Mac os x lion -Installation error | MacRumors Forums This lists several arguments each beginning with double-dashes and explains what each does. Drag this file into a Terminal window and add -usage to the end. Yes, running a macOS installer takes several times longer than block-copying an image to a computer, but the tradeoff is better security and performance. That can lead to stability problems and unexpected results. Fix MacBook Pro Error Code and MessagesĪ lot of what makes macOS work with Mac hardware is now based on firmware updates. Apple is killing the concept of imaging a Mac. We can use it to erase a Mac and reinstall macOS. How to Fix 'macOS Could Not Be Installed on Your Computer' Error.