Mac fans stuck on full blast
My iMac (27-inch, Mid 2010) started crashing when asleep, and now its internal fans are stuck blowing at full speed, even after resetting its SMC. What’s wrong with it?
Shut down your iMac, leave it to cool off for 10 minutes or so, then start it up in Apple Hardware Test (see apple. co/2b3FhpK for instructions on how to access that; you may need the install discs that came with your Mac).
If that tool’s test results check out as normal and your Mac’s fans stay full on, reset the SMC and then its NVRAM. To do this, shut down your Mac, unplug the power cord and disconnect all peripherals apart from any Ethernet cable and your keyboard and mouse. Plug the cord back in, get your hands ready to hold down
Alt+ and start up your Mac. As soon as you hear the startup sound, hold down those keys until you hear the sound a second time, then release them, and allow the Mac to start up as normal. You may need to correct settings such as volume and display afterwards, but the fans should drop back to normal. If not, take your iMac to a Genius Bar for a complete check-up. Further crashes during sleep may disappear in Safe mode (hold ß at the startup sound); this turns off third-party extensions, which should tell you if one of them is to blame.
Sidebar favorites in dispute
The two versions of Finder’s sidebar, listing Favorites, Devices, and so on, have somehow become different on my Mac running OS X El Capitan 10.11.5. Viewed in Finder, that sidebar looks correct, with a single Desktop item. However, viewed in an app’s Save dialog, the Desktop item is shown twice under Favorites. Why is this, and how can I fix it?
This shouldn’t be possible, as both those sidebars are generated by the same code in OS X, and should be identical. To verify that, start an app, create a new document, then open the Save dialog, positioning it on the left of your screen. Then bring a Finder window to the front on the right, so that you can see both sidebars at once.
Next, choose Finder > Preferences and click the Sidebar tab. Uncheck the Applications item there; that item should immediately disappear from Favorites in Finder and the Save dialog.
Sometimes such preferences get stuck, and trashing the file at ~/Library/ Preferences/com.apple. Finder.plist (the “~” means your home folder; in Finder,
hold Alt and choose Go > Library) can allow it to be saved properly. However, the two locations’ behavior should remain consistent and reliable even if the preferences can’t be saved properly.
If the two sidebars don’t behave identically, your Mac most probably has the remains of an old third-party utility that modifies Save dialogs, such as Default Folder X. Restarting in Safe mode (hold when you hear the startup sound) should disable that so you can confirm this, allowing you to identify and remove those remains later.
Back to the recent past
Is it possible to revert to running OS X El Capitan 10.11.3 from the current 10.11.6 version?
Yes, although it is complex to say the least, and exposes your Mac to security risks. You’d need to install El Capitan from scratch, and then update it using the Combo installer for 10.11.3 before manually restoring your apps, documents, and so on, from your Time Machine backup. Bear in mind that some current versions of apps might not work even then.
Black screen iMac lockout
At seemingly random times, the display of my iMac (21.5-inch, Mid 2011) goes completely black, and the system is then unusable, so I have to perform a forced shutdown using its power button. This iMac has a Radeon HD 6770M graphics card. Why is this happening?
Given the Mac’s vintage, a dying graphics card or other hardware could be to blame. Several models of graphics cards have suffered premature failure – probably because of the introduction of lead-free solder – and some have had their warranties extended as a result.
Before you take the Mac in for repair, check its logs in Console. After this next happens and the Mac has restarted, open Console and search for BOOT_TIME, which should take you back to the last startup. The entries right before that may give a better idea as to what went wrong at the time of the black screen. Otherwise, run Apple Hardware Test or Diagnostics; if that reports a hardware fault, you’ll need to take the Mac for repair. If the hardware checks out, the Mac could still have a graphics card problem, which may only be possible to fully diagnose with Apple’s in-house tools.
The Mac may be inadvertently trying to enter Target Display Mode (as when you press You might stop that by temporarily restarting in Safe mode, or by checking the settings in the Displays preferences pane.
Stop following me
Can macOS block internet tracking?
In System Preferences, the Security & Privacy pane’s Privacy tab has a Location Services item, where you can prevent apps determining your location, but to stop browser-based