Sluggish and unresponsive macOS behaviour with external HDD / SSD drive attached

Is your mouse jumpy, are you unable to select menu items or double click icons, does it feel like your computer is so slow it’s not catching up ….

It could very well be that Spotlight is indexing your external hard drive and takes up too many resources doing it.

Although you would expect indexing should never affect the user experience … unfortunately it does, and the only way to work with your computer is to open System Preferences, go to “Spotlight”, the “Privacy Tab”, and add your external HDD / SSD to the list.