Why is the Lock feature not working on my folder? I have a private folder on my drive that I keep personal docs in and i want to make it password protected. So I thought I would click Get Info > make it write only in the Sharing &amp; Permissions section > lock it in the General section, then click the padlock at the bottom corner to prevent changes, which means if anyone wants to get access to the folder, they would have to click the padlock, type in a password, uncheck the Locked tick and then change the permissions to read &amp; write.

This worked for a while, but now when I access the folder, I go through all those steps and when I click the padlock, I don't hear the locking noise and I can still make changes to the folder.

Is there a setting somewhere that I need to fix/unfix? Is there something in Terminal I can do to make this folder password protected?
If your goal is to prevent someone accidentally stumbling into a folder, making the folder un-readable through the Finder dialog would likely accomplish that goal (and without needing a password — one is unlikely to "accidentally" open the File Info dialog, change the permissions settings, then open the folder.

If you are concerned about some snooping that isn't quite accidental, you really need more protection. I'd recommend using an encrypted disk image. That way you can give your folder real password protection, and the password you use doesn't have to be the system password (which users of your computer might need to know).