Troubleshooting

You dragged it to the Trash and macOS refused, or it came back on its own. Here is every reason a Mac app won't delete, in the order it usually turns out to be, with the fix for each one and an honest answer for the case you can't fix yourself.

Press Option-Command-Esc. That's the Mac's Ctrl+Alt+Delete, and it opens the Force Quit window. Here's every way to close a frozen app, in ascending order of force, and what to do when force quitting itself stops working.

Find out what's using your Mac's network: Activity Monitor's Network tab for per-app data, nettop and lsof for live connections and hosts, and how to see which app is quietly phoning home.

A slow Mac is almost always one of four things: memory pressure, a runaway process, too many login items, or background work after an update. Here's how to tell which, and fix the real cause.

accountsd using high CPU on your Mac is the Accounts daemon stuck in a broken sync loop, almost always one iCloud or mail account. Here's how to find the offending account and fix it.

backupd using high CPU on your Mac is Time Machine running a backup, usually normal and self-throttling. Here's when it's expected, when it isn't, and how to bring it back under control.

bluetoothd using high CPU on your Mac isn't normal. It's almost always a specific flaky Bluetooth device or an OS bug. Here's how to isolate the device and the fixes that actually work.

cfprefsd using high CPU on your Mac is the preferences daemon, and it's almost always a badly behaved app or a corrupt preference file. Here's how to find the culprit and reset it safely.

coreaudiod using high CPU on your Mac is Core Audio, and it's usually a symptom of another app monitoring the mic or a buggy audio driver. Here's how to find the real cause and reset it safely.

lsd using high CPU on your Mac is the Launch Services database daemon: the registry of which app opens which file. Here's why it spikes, how to rebuild the database, and why it's not launchservicesd.

mdworker and mdworker_shared using high CPU on your Mac are Spotlight's indexing workers reading your files. Here's why they spike, why several at once is normal, and the safe fixes.

mediaanalysisd using high CPU on your Mac is the on-device engine behind Live Text and Visual Look Up, not face recognition. Here's why it spikes, why it's private, and how to calm it down.

sharingd using high CPU on your Mac powers AirDrop, Handoff, and Continuity, and usually spikes on a stuck AirDrop or constant wireless retries. Here's how to calm it, and the privacy angle worth knowing.

softwareupdated using high CPU on your Mac is the Software Update daemon checking, downloading, or installing updates. Here's why it sometimes gets stuck, and how to fix it safely.

syspolicyd using high CPU on your Mac is Gatekeeper checking apps as they launch. Here's why it spikes (often an app launching binaries in a loop) and the safe way to calm it.

trustd using high CPU on your Mac is the certificate-trust daemon checking whether certificates are still valid. Here's why it spikes or hangs, and how to fix the persistent 100% case.

Mac slow after a macOS update? It's usually temporary background work (Spotlight reindexing, Photos re-analyzing, iCloud re-syncing), not a broken Mac.

Documents taking up space on your Mac? That storage slice is broader than your Documents folder: it counts big files across your whole home folder. Here's how to shrink it.

'Not enough space to update macOS' with several GB free? A macOS installer needs far more room than the download. Here's how much you need and how to free it.

MacBook fans loud and running hot? Fans spinning up under load is normal; the fix is finding which process is working the CPU or GPU. Here's how to check.

Why is my Mac storage full when you deleted everything? Because APFS snapshots retain old blocks, space stays purgeable, and 'System Data' won't budge.

WindowServer high CPU on a Mac isn't a virus; it's the process that draws every window and pixel. Here's why it spikes and how to bring the load down safely.

Deleting files but not freeing space on Mac? Causes are an un-emptied Trash, APFS snapshots, purgeable space, or a stale Finder count, plus the fix for each.

High kernel_task CPU on Mac usually isn't a virus; it's macOS managing heat by holding back the CPU. Here's why it spikes, what's normal, and the safe fixes.

The 'startup disk almost full' warning on your Mac isn't just a nag; APFS needs real free headroom. Here's what triggers it and how to clear room safely.

Port 3000 already in use? Here's how to find the exact process holding it on macOS with lsof, stop it safely, and deal with zombie dev servers that survived Ctrl-C.