Why does my mac keep saying Error 36?

"I want to move my Iphoto photos to my external hard drive.... I have OS Sierra.... Error 36 shows"

OK, here goes with "Computer Use 101" class.

Lesson 1: You do not have iPhoto and OS X Sierra. Figure out which of those is correct. iPhoto was replaced by the Photos app before Sierra was released.

Lesson 2: You cannot move a file from one storage / drive to another. You can copy files. The originals do not move; they stay put. If you don't need the originals after copying, drag them to the trash.

Lesson 3: You cannot normally see any photo files in the iPhoto app. The files are inside the app and since the app is not a folder, you cannot normally see the files. If you drag a selection from the app window, the copy will be 72dpi resolution like a screen shot. That means if the original is 72dpi resolution, it will be an exact copy. If the original is higher resolution, it will be reduced to 72dpi. To use a photo on a FaceBook page, that's probably fine. To have the highest possible quality for printing, don't do it like that. Instead, select the photo in the window and then File > Export Unmodified Original".

Lesson 4: Be sure you are wearing your glasses when you read an error code. For example, "Error 36" is not the same as "error -36". I will assume you made a mistake and it is really "error -36".

"I've heard Dot Clean.... Disk warrior.... carbon cloner.... time capsule.... Onyx"

Just say "NO" to all of these. You do not need any utility to copy files.

Since I'm not sure what you have, my answer is for Photos. Note that I always capitalize proper nouns, unlike you kids.

Do this.....

– Launch the Photos app.

– Select one photo (not all of them) and press ⌘ I (for information).

In the info window, just below the title (or "Add a title"), you will see the actual file name. For most users, every file name will end with ".jpg".

– If all of the characters in the file name are normal A to Z letters or zero to 9 numerals or dash or space, it's fine. For any other characters, such as those you get from trying to post a curse word on a web forum (%&!#! and such), this is the reason for error, invalid file name. The solution is to rename the file.

– In a Finder window, press ⌘3 to view as columns (for easy navigation).

– Select your home folder at the left sidebar. If your finder preferences do not allow the home folder to appear, select the startup partition/Users/your home folder.

– Select the Pictures directory.

– Right-click (control-click) the "Photos Library.photoslibrary" bundle and choose "Show Package Contents".

– Navigate to Contents/Masters/2017 (or whatever year) and so on to see the individual files.

– For any with invalid characters, rename the file to eliminate invalid characters. Note: Foreign language characters typically are valid, such as "生日聚会.jpg". Different lists of invalid characters apply to OS X, Terminal, Finder, and Darwin, but / and : will be forbidden in all these.

– After all invalid filenames are corrected, drag 10 or 20 at a time to the external drive. By dragging in smaller groups, you will get an error message for just that group, which will make it easy to locate the bad filename. Although this will take longer than dragging the entire group, it beats asking several online forums for help and getting dumb answers, such as "Try Carbon Copy Cloner".

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