In this practical tutorial episode, Siddarth Mahajan demonstrates how to turn a folder into an encrypted disk image (.dmg) file on your Mac, useful if you, for example, need to temporarily share your Mac with someone else and want to protect particularly sensitive data on it. To do this:
- Open Disk Utility (located in the Utilities folder).
- Choose File > New image > image from folder (or press Command-Shift-N), and select the folder using the standard open dialog.
- In the resulting dialog, choose the level of encryption you want for the image in the "Encryption" popup menu (a higher level is slower but more secure) and enter a password that will be used to access it.
- Click Save, and once Disk Utility reports that the operation is successful, click Done. The image will be saved to the location you specified, which is by default the location of the original folder. Be sure to delete the original folder at this point, so that the data can only be accessed through the password-protected, encrypted disk image.
To access the image, open it and enter the password you chose. The folder will then be mounted like a volume on your desktop, where you can add, modify, and delete its contents. When you're done, be sure to eject it so that it can't be accessed without a password by selecting it on your Desktop and choosing File > Eject (or pressing Command-E).
Useful Links:
- macOS Disk Utility: https://support.apple.com/en-us/HT201250
- Email Siddarth: [email protected]
Transcript
Disclaimer: This transcript was generated by AI Note Taker – VoicePen, an AI-powered transcription app. It is not edited or formatted, and it may not accurately capture the speakers’ names, voices, or content.
Siddarth: Are you in that situation where you need to give your Mac to someone for maybe a few hours or a few days, but worried about what if they might access my private files, my private folders? Of course, everyone has their own privacy, right? You might have private documents or messages or pictures, videos, whatever.
Siddarth: Do you know that we can lock or we can encrypt the folder on Mac with a password? Well, if you don't know that, yes, we can actually do that. How can we do that? That's what I'm here for. I'm Siddharth Mahajan. In this episode, I'll be demonstrating that. How can we encrypt a folder with a password on our Mac? So let's get started.
Siddarth: I'm on my desktop here.
VoiceOver: Siddharth Private Files folder.
Siddarth: This is my folder, Siddharth Private Files.
VoiceOver: Siddharth Private Files folder.
Siddarth: Let me press Vivo space to open.
VoiceOver: Finder has new window.
Siddarth: Okay, let me interact.
VoiceOver: In list view, table.
Siddarth: What are the files here?
VoiceOver: CFP underscore green humanities dot PDF.
Siddarth: One of my CFP files.
VoiceOver: conference PDF.
Siddarth: Apple's pages document, I was reading one of the guides here. So I have these two files. Suppose I want to lock this or I want to encrypt this with a password. How can I do that? Let me close this with command W. Let's open disk utility, command space for a spotlight.
VoiceOver: Spotlight.
Siddarth: And I'll type disk.
VoiceOver: P-I-S-K. Start up disk utility. Completion selected.
Siddarth: Yes. Let's hit enter on this.
VoiceOver: Finder. Disk utility. Disk utility. Window. Disk selection table.
Siddarth: All right. We are in disk utility. Let me hit V-O-M to open the menu.
VoiceOver: Apple menu.
Siddarth: right arrow we have to enter file menu disk utility menu another right file menu i'll press down arrow till i get new image sub menu new image sub menu let me press right arrow to open this menu new image sub menu blank image ellipsis command and no we don't want this image from folder ellipsis command shift n image from folder this is the option which we need let me hit return key or vivo
Siddarth: whatever you are comfortable with now we are in the standard um file uh how we open the files right so we need to select that folder here which we want to lock so let me interact here in dialogue open list view table i'll go to desktop date added now i'll interact again here scroll your vertical sidebar table inside bar downloads desktop document desktop yes i'm already on
VoiceOver: desktop, un-interact. Scroll area, interact.
Siddarth: I'll interact here another time in list view.
VoiceOver: Yes, this is the one we need, right?
Siddarth: So, Vivo space, un-interact. Choose button. So, I press Vivo plus right arrow. I'll hit enter on choose. Let's see what we get.
VoiceOver: It starts private files. Content selected. Save as. Edit text. Save as. Tags.
Siddarth: We got the save as. We'll go to right. We will write.
VoiceOver: Tags. Tags. Where? Desktop. Show more options. None. Encryption. Pop-up button.
Siddarth: We need to change this encryption pop-up. We need to change from none to 128.
VoiceOver: So let me hit view a space.
Siddarth: Yes. If I hit space on this or view a space on this.
VoiceOver: It's asking us to enter the password.
Siddarth: So basically there are two password fields here. One is the password and again a confirm password. Let me just type 1, 2, 3, 4, 5. I'll press tab.
VoiceOver: Verify. Secure edit text.
Siddarth: Again, verify password.
VoiceOver: 1, 2, 3, 4, 5.
Siddarth: If I press tab. Show password assistant button. I'll press tab again. Cancel button. Choose button. I'll hit the workspace and choose. 128 bit AES encryption. Encryption. Pop up.
Siddarth: We'll just go all the way to the end.
VoiceOver: Save button.
Siddarth: And we click on save.
VoiceOver: Collapse. Disclosure triangle. Creating folder disk image SIDARTH private files dot DMG. Running. Show details. Dimmed. Operation successful. Collapsed. Show the done. Done.
Siddarth: OK. Operation successful. It had done.
VoiceOver: Disk selection table.
Siddarth: OK. We'll close this. We don't need this anymore.
VoiceOver: Authentication.
Siddarth: Now, what happened is it creates a DMG file, an encrypted DMG file, To open that file, we need to enter the password.
VoiceOver: So there are two files here now on my desktop. This is the folder earlier which we had.
Siddarth: This is the encrypted folder. Let me view a space on this and let's see, will it ask a password?
VoiceOver: Whoa, so it's asking password.
Siddarth: Let me hit 1, 2, 3, 4, 5, and enter. Let me check by interacting. Do we have our file?
VoiceOver: Well, we have the encrypted file. Now, I'll close this.
Siddarth: So we have a volume here. So now we can eject this volume by pressing command E. Okay.
VoiceOver: We have only folder. We don't want this folder as well. Let's delete.
Siddarth: And we have only. If I hit again, we will space.
VoiceOver: Okay.
VoiceOver: Enter a password.
Siddarth: Hope this short demo was helpful for you. If you have any questions, contact on my email ID. My email ID is S-I-D-D-A-R-T-H-M-A-H-A-J-A-N 15 at gmail.com. Have a good day.