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This page last modified 2021.10.10 16:46

OS X Annoyances

See also Linux Annoyances for Terminal on Mac

Catalina annoyances

Zoom Screen Sharing doesn't Work
Zoom: exclamation point in triangle - enabling screensharing permissions
If you try to share your screen, you may see a triangle with exclamation point in it. This is because MacOS Catalina added a new category of app permissions called “Screen Recordings”. This prevents a user from being able to share their screen through an app until permission is given specifically for that app. If you have NOT granted this permission, then if you try to share your screen through the Zoom app, there will be error images instead (showing an exclamation mark inside of a rectangle, instead of a preview of what you might be able to share)

To fix this:

  1. Settings
  2. Security & Privacy
  3. Privacy tab
  4. Screen Recording
  5. You may need to Unlock in lower-left of dialog (and provide password)
  6. Allow Zoom, or other apps you want to be allowed to use your screen
  7. Then lock
  8. You may need to restart Zoom.

Zoom Camera Doesn't Work

MacOS Catalina prevents the camera from being used until permission is given specifically for the app (such as the Zoom app). This is requested the first time you join a Zoom session:
“” would like to access the camera“
This is similar to the above (screen sharing). To fix this:

  1. Settings
  2. Security & Privacy
  3. Privacy tab
  4. Camera
  5. You may need to Unlock in lower-left of dialog (and provide password)
  6. Allow Zoom, or other apps you want to be allowed to use your camera
  7. Then lock
  8. You may need to restart Zoom.

Change default application

Suppose you want all .xlsx files to open with LibreOffice instead of Numbers. Do the following.

  1. Find a file with the extension (.xlsx), right click, and Get Info.
  2. Under Open with, open the dropdown, find the application you want to open this type of file (LibreOffice), and select it.
  3. Click the Change All… button.
  4. Confirm that you want to make the change.

From this point on, all files with the same extension will open with this application.

Reset Printing System

If something goes wrong with printing, for example a bad file descriptors error, you need to reset the printing system. If you reset the printing system, you will

  • lose all print queues and pending print jobs
  • remove all printer preference files
  • removes all printers currently in the Printers & Scanners preference pane.

To Reset Printing System:

  1. Launch System Preferences
  2. Select Printers & Scanners
  3. In the Printers and Scanners preference pane, place your cursor in an empty area of the printer list sidebar (where the printers are listed) and right-click; select Reset Printing System from the popup.
  4. You're asked to confirm. Press Reset.
  5. You may need to enter administrator password or finger.

The printing system will be reset and you will need to add back your printer.

Determine IP address of Samsung M2830DW printer

  1. Turn device on
  2. Press and hold the Cancel (X) button till green light blinks 5 times, then release
  3. Output is printed. On second page you'll find the IP address.

Play a DVD .iso image

Leawo Blu-ray Player works.

  1. Mount the .iso (right-click on .iso file, )
  2. Run Leawo
  3. See: Open File and the DVD you've mounted
  4. Right-click on the DVD you want to play
  5. Play Disk

MacBook Beeps Often

This is likely an alert that you have received new mail. To check and remove this:

  1. Open the Mail app
  2. Select Mail > Preferences
  3. General tab
  4. In the drop-down menu next to the New messages sound, select your favorite sound or None.

iTunes Playback skips -- skims -- music

20190905 Have seen videos that playback super fast when there is audio in the file. Also happens when watching YouTube videos.
Problem solved by

  • Open Activity Monitor
  • Under CPU tab, find coreaudiod process, and click to select it.
  • Click the X-in-stopsign button upper left of the Activity Monitor screen, and Force Quit.
  • coreaudiod will restart and videos will play just fine.

20190923, happened again. Did the above, problem solved.

See all running applications with force-quit

This from

  • Force Quit Applications window: Command+Option+Escape to summon the basic “Force Quit Applications” window (a simple task manager for OS X). Only shows windowed-applications.
  • Activity Monitor: Shows all applications in addition to windowed ones. Command+Spacebar type “Activity”. Select an app, use the X n upper left to bring up dialog allowing quit and force quit choices.
  • top: Run Terminal, command=top. Sort by cpu or memory usage: top -o cpu [or] top -0 rsize
  • ps: Run Terminal command=ps ps aux [or] ps aux | grep process

View or Change a Program's Properties

Property files are stored in /Library/Preferences. Run Terminal to work with. From

Following is example for Time Machine, limiting its disk use.

Time Machine by default will use all the available disk space on your backup drive. The good news is that you can setup a maximum limit that Time Machine can use. All you need to do is specify in megabytes the maximum space limit. You can do this by multiplying your Gigabyte preference by 1024 bytes. For example if I wanted the maximum backup space to be 100GB, I would multiply 100 by 1024 which equals 102400. I can then enter this terminal command:

sudo defaults write /Library/Preferences/ MaxSize 102400

This preference can be viewed within the /Library/Preferences/ file by

sudo defaults read /Library/Preferences/

To remove the limit, use the following command:

sudo defaults delete /Library/Preferences/ MaxSize

Can't Delete File Because There's Not Enough Space

You want to delete files because the disk is full, but OS X won't let you do this because the disk is full.

  1. Reboot the Mac, and while it's rebooting press and hold Command-R
  2. When the MacOS Utilities window appears, select: Disk Utility and click Continue
  3. In Disk Utility, select the disk that's causing the issue, and use First Aid to look at and repair the disk.
  4. When this finishes, you can First Aid another disk.
  5. Then quit the disk utility and restart your Mac.
  6. Then empty the trash.

How much space is each subdirectory using?

For example, you have lots of subdirectories in your Videos directory, and how can you determine which is using the most space?

  • Start Terminal
  • Change to the directory you want to look at (for example, cd Videos)
  • Enter the command du -hcd 1
    • du disk use
    • h human readable form
    • c show a total for the directory
    • d 1 depth, 1 means only top level, the subdirectories in the current directory

To use this and get a sort based on size: du -hcd 1 | sort -h (the -h on the sort reads first column as human readable values, that is it treats 800M < 1G as you would expect)

Burn an ISO file to Bootable USB

Digested from link

20191213 This did not work for me: I'd downloaded the Win10 ISO and followed instructions to create a boot USB stick.  The USB stick wouldn't boot. However I was able to use [[]] on a Windows machine to create a bootable USB stick.

You have an ISO file and you want to make a bootable USB stick from it. You will need a USB stick larger than the ISO file (e.g., ISO is 6GB, you can use a 8GB or larger USB drive. When done, the drive is completely full.)

  1. Run terminal
    diskutil list
  2. Find name of the USB stick (e.g., /dev/disk4; we'll use /dev/diskX here)
  3. diskutil unmount /dev/diskX

    or if that doesn't work do

    diskutil unmountDisk /dev/diskX

    you should see a message saying unmount was successful.

  4. Now go to finder and locate the ISO file. Right-click, and Copy <filename> as Pathname.
  5. Back to terminal, enter part of command (don't press enter yet)
    sudo dd bs=1m if=

    and then paste the pathname of the ISO file to the command and then add of=/dev/rdiskX

  6. For ISO file in smi's download directory with name silly.iso the command will look something like
    sudo dd bs=1m if=/Users/smi/Downloads/silly.iso of=/dev/rdiskX
  7. When it completes, type
    diskutil eject /dev/diskX

    see “ejected” message and unplug the USB stick.

bs is block size
if is input file
of is output file

Takes about 2 minutes to write a 6GB ISO file to a USB 3.1 drive.

20191213 I downloaded a Windows 10 ISO file from
You can find other Windows versions to download, see

20201216 Success burning Linux Mint 20.1 to USB drive on iMac.

  1. Get your iso, suppose it's in Downloads.
  2. Insert your USB drive (make sure it's big enough)
  3. Run Disk Utility, get the device name.
  4. Run Terminal. Device many show as disk3s1
  5. ls /dev/disk*
  6. Find the disk without the s1. Suppose it's disk3
  7. sudo dd if=Downloads/linuxmint-20.1-cinnamon-64bit-beta.iso of=/dev/disk3
  8. A 2GB iso file took about 40 minutes to complete; the dd command tells records in and out, bytes transferred, and how long it took. Be patient.

(Note that Mac OSX may be unable to mount the USB drive when this is completed, and that's ok.

Burn an ISO file to Bootable CD/DVD


  1. Open Finder window, navigate to your ISO file, single-click to select it
  2. File > Burn Disk Image
  3. Insert disk if you haven't already; click Burn

Alternatively you can right-click on the ISO file and Burn Disk Image

(For OS X 10.10 and earlier) From Umass link

  1. Applications > Utilities > Disk Utility
  2. Insert blank CD/DVD
  3. Drag the *.iso file from a Finder window to the Disk Utility window, drop in left pane in the empty area below the Mac drive names.
  4. Select the .iso file name in the left pane of Disk Utility, and click Burn (top left).
  5. The Burn Disk In: window opens and shows your CD/DVD as destination
  6. Click Burn
  7. When done the disk will eject

Active Window is Covered

Suppose you're running Resolve and trying to archive a project, and maybe try to rename it. You can see that the Finder window for storing the project is the active window and it's also covered by the View Projects window, it's impossible to get to it. I figured out what to do on 20200105.

  1. Hold down Alt/Option key, move mouse to the Corner of the (Resolve main) window; see double arrow ←→ appear, double-click.
  2. Move the main window out of the way (to another monitor for example)
  3. For the monitor with the View Projects window is covering the Finder window, switch desktops away and then back.
  4. The Finder (hidden) window will appear; quickly drag this so it's outside the covering View Projects window.
  5. You can then work on the no-longer-hidden Finder window and continue.

Enter/Exit Full Screen Mode

To enter full screen mode:

  • Press green button in upper left
  • Control-⌘-F

To exit full screen mode:

  • Control-⌘-F
  • Move mouse to upper-left corner and let it sit. You'll see green button, press it.

To work in bigger window without going full screen

  • Press and hold Option key while click on the green button in upper left
    • Window expands, menu and dock remain visible
    • To exit, press and hold Option key and click on green button again
  • Or double-click on the app's title bar

exiting full screen mode in DaVinci Resolve isn't working – once I put Resolve in full-screen, I can't get it to exit full screen mode. [20200208]

Screen Shot Mods

Shift-⌘-4 Take screenshot of area on screen you identify

In terminal mode

defaults read current screen shot options
defaults write type jpgchange screenshot file type to jpg. Other options are: bmp pdf jpg tif pict tga png
defaults write name Georgechange from “Screen Shot 2020-07-02…” to “George 2020-0702…“
using “George 1” precedes with George 1 instead
defaults write location Users/smi/Pictures/Screenshotsstores there instead of desktop
defaults write “include-date” 0removes the date and time from the screenshot

and be sure to do this to load the settings (or reboot):
killall SystemUIServer

Dock Tricks

Add space to Dock

You want to add one (maybe more – repeat if so) space to the dock so you can group the icons on the dock. This from here

  1. Launch the terminal app. (It's in Applications/Utilities)
  2. At the terminal prompt, type this command: defaults write persistent-apps -array-add '{“tile-type”=“spacer-tile”;}'; killall Dock
    1. This will cause the Dock to reboot (go away and return) but now there'll be a space in it.
    2. Click and drag the space to where you want it.
    3. Repeat to add more spaces.
    4. To remove a space, right-click or control-click it and select Remove from Dock.

Add Recent Applications to Dock

Add an icon to the Dock, like that for Downloads (shows recent downloaded files), that holds list of recently run applications. (Similar to previous item here.)

  1. Launch the terminal app. (It's in Applications/Utilities)
  2. At the terminal prompt, type this command:defaults write persistent-others -array-add '{ “tile-data” = { “list-type” = 1; }; “tile-type” = “recents-tile”; }'; killall Dock

Highlight hidden apps in Dock

defaults write showhidden -bool yes; killall Dock

Interesting Software and Applications

Monkey Bread Software. Has TreeSize and Show IP in menu bar.

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Convert several files to one PDF file

You have a number of files that you want to combine into a single PDF file.

  • Maybe you have scanned 2-sided pages from a document, fronts then rears, and want to make a single PDF
  • Maybe you have pictures you want to combine into a PDF

Let's assume all files are JPGs.

Here's what you can do. From How To Geek link

  1. Open the Preview app. (Search using Spotlight (Command-spacebar) or in Applications directory)
  2. Preview will prompt you to open file(s). Go to the directory holding the images you want to combine, and select them all using the Command key to select multiple images. Then, click the Open button. make sure that View Thumbnails is enabled else set it and repeat this step
  3. In the Side bar, move the images into the order you want.
  4. When you're happy with their order, select File > Print
    1. Look through the images. If any are not correctly oriented, go to that picture and Show Details
    2. There you can change Orientation and Turn on/off Auto Rotate.
  5. Click the PDF dropdown, and choose Save as PDF.
  6. In the Save As dialog, give the PDF file a name, title, etc and specify where to save it.
    1. You can add a password to the PDF, click Security Options.
  7. Then press Save.

If you want to change things (add/delete images, re-arrange them) then open the PDF you created in Preview, and select View > Contact Sheet or View > Thumbnails and add/delete and re-arrange. Then save from the file menu.

Restore Old iMac or MacBook

You have an old iMac or MacBook and a disk that is blank, either it didn't come with the machine or it has been erased. You want to get the machine running MacOS.
The players here: ABCD=Old iMac or MacBook you want to fix. EB9U=Running MacOS machine.

The process is:

  • Get info about the old iMac or MacBook (we'll call the machine ABCD).
  • Determine what MacOS versions can run on the ABCD machine.
  • Get a TimeMachine backup from another iMac or MacBook that is running a version that can run on the old one (we'll call the machine EB9U).
  • Boot the old ABCD machine and restore the MacOS from the TimeMachine backup of EB9U.
  • Modify the ABCD machine name and other parameters to distinguish it.

We'll go over each of these steps in turn.

Get info about the old iMac or MacBook (ABCD)

  1. Enter the old device's (ABCD's) serial number
  2. Do the Captcha
  3. The information reported will show an ID. The ID is of the form “iMac 10,1”.
  4. It's a good idea to write down the other information and attach it to the ABCD machine.

Determine what MacOS versions can run on the old ABCD machine.

  • You can do a DuckDuckGo (or Google) search to see what MacOS will run on your machine.
  • For the purposes of this section, we'll assume that the machine is 10,1 or greater and not 19,2 or greater and that your EB9U machine is running High Sierra 10.13. High Sierra can run on this machine.

Get a TimeMachine backup from another iMac or MacBook that is running a version that can run on the old one.

  1. Supposing you have a machine (we're calling EB9U) running High Sierra and the ABCD machine can also run High Sierra (and you may have determined this in the previous step.
  2. Perform a TimeMachine backup of the High Sierra machine (EB9U) onto a removable disk USB disk.
  3. When the backup completes, disconnect the TimeMachine backup disk.
  4. Power off the EB9U machine.

Boot the old ABCD machine and restore the MacOS from the TimeMachine backup.

  1. Connect the TimeMachine backup (from EB9U) to the old machine ABCD.
  2. Make sure that the EB9U machine is powered off (or at least disconnected from the network).
  3. Power on the ABCD machine and hold down the Command (⌘) and R buttons (this is the Windows key on a non-Mac keyboard). You may be holding these keys down for several minutes.
    1. See for details on booting to recovery mode.
  4. Keep holding these keys down after the Apple logo appears, until the Recovery screen appears.
  5. In the upper-right of the screen (on ABCD) you may see a way to connect to WiFi. Do this.
  6. Select the “Restore from Time Machine backup” option
  7. Select the Time Machine backup drive and the backup on that drive to restore from, and OK. You may have other confirmation messages to OK.
  8. The restore may take some time, maybe an hour. Continue after the restore completes.

Modify the ABCD machine name and other parameters to distinguish it.

  1. Rename the ABCD machine.
  2. Change user and login information on ABCD.
  3. Go through the Settings (Select the Apple and System Preferences) and adjust as necessary on ABCD.

Terminal goodies

Mac uptime and reboot history last reboot
What is my IP address ifconfig

iMac Reboots every day

I upgraded a late 2012 iMac 13,1 to have more memory and SSD. After the upgrade, the machine running Mojave 10.14 would reboot almost once a day indicating problem with Network or other issue. The machine would run otherwise, but I wanted to see how to keep it from rebooting. From a variety of sources, I tried all of the following in the order shown, and only after the last thing I tried did the machine stop rebooting daily.

  1. Uncheck put hard disks to sleep when possible
  2. Set wake for network access to Off
  3. Reset SMC
  4. Reset NVRAM
  5. Switch local Wifi networks
  6. Terminal commands: sudo pmset standby 0 <and> sudo pmset autopoweroff 0
  7. Terminal command: sudo pmset -a standby 0
  8. System preferences > Energy Saver: Don't put Hard Disks to sleep when possible (uncheck it)

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os_x_annoyances.txt · Last modified: 2021.10.10 16:46 by Steve Isenberg