Try as I might, but I couldn’t for the life of me put a folder in iCloud named “Dropbox”. As it turns out, it’s not just “Dropbox” — people have found out that Apple maintains a blacklist of file and folder names which customers should avoid using at all cost in their iCloud Drive.
“Today I learned that if you put a folder named ‘Dropbox’ in your iCloud Drive, iCloud refuses to upload it,” according to Ole Begemann, via Michael Tsai. “It only says ‘Ineligible'”.
I’ve also tried “dropbox”, no cigar. It happened when trying to create said folder via the Files app on my iPhone. On the Mac side, interestingly, you are allowed to create an iCloud Drive folder named “Dropbox” via the Finder but macOS prevents you from actually using it.
Today I learned that if you put a folder named “Dropbox” in your iCloud Drive, iCloud refuses to upload it. It only says “Ineligible”.
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Other blacklisted folder names include “OneDrive” and “IDrive-Sync”.
Now, it would be all too easy to conclude that Apple is banning certain iCloud file/folder names for competitive reasons. After all, its late co-founder Steve Jobs refused to acquire Dropbox when they were shopping around Silicon Valley, relegating them to nothing but “a feature”.
I wish it was that simple, but it isn’t. Besides, Apple isn’t that petty.
So you can’t put your Dropbox folder inside your iCloud folder.... mmm nice one apple. Nice one.
It’s necessary from a technical standpoint. Mixing two sync services together is a recipe for disaster. You could end up in a state where two clients are fighting over the same data, causing an endless loop that could bog down your system and your bandwidth.
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The reason for this is prosaic and has to do with the fact that Apple wants to avoid any confusion or, worse, system errors stemming from allowing special names for iCloud items. Some of the blacklisted file names are known to cause issues with not just Mac and Windows PCs, but networks too (another reason for this could be the local Dropbox folder that macOS creates in order to facilitate easy sharing between macOS user accounts).
TL;DR: it’s a technical issue, not a political one.
That would explain a bunch of other system-reserved names for iCloud Drive files and folders that software engineer Flo Vimart recalls seeing after decompiling the iCloud Drive binary.
I recall de compiling the iCloud Drive binary and seeing “Dropbox” string part of a blacklist.
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The full list of disallowed iCloud names was posted to Stack Exchange by Malcolm Hall:
Filename:
- is
.DS_Store - begins with
(A Document Being Saved - contains
.nosync(in any case) - is
.ubd - contains
.weakpkg - is
tmp(in any case) - is
.tmp(in any case) - is
desktop.ini(in any case) - begins with ~$
- is
Microsoft User Data(in any case) - is
$RECYCLE.BIN(in any case) - is
iPhoto Library(in any case) - is
Dropbox(in any case) - is
OneDrive(in any case) - is
IDrive-Sync(in any case) - is
.dropbox(in any case) - is
.dropbox.attr(in any case) - is
icon\r(in any case)
Extension is (in any case):
tmpphotoslibraryphotolibraryaplibrarymigratedaplibrarymigratedphotolibrarymigratedaperturelibrary
NOTE: Extension is more than two characters and filename is
~.
Tsai advised that adding an empty file named “.nosync” to an iCloud folder prevents it from syncing, which could be quite useful as a method of selective syncing. If that doesn’t work, other people have suggested renaming the folder to end in “.nosync”. Another cool tip for you: iCloud folders that are named “tmp” or end with “.tmp” are not synced either (if an item isn’t synced, you’ll see a cloud icon with a line through it in the Finder).
Recursion. Mixing two sync services could cause you to enter a state where they will fight over data constantly. Plus, there’s often hidden files necessary for each service to run, but would cause havoc for the other.
In short, it’s to protect users.
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Cult of Mac‘s Charlie Sorrel observes that the iCloud exclusion list is actually a smart move that could save people from headache down the road.
What’s happening here? Well, the practical answer might be that Apple is preventing users from dragging their entire root-level Dropbox folder into iCloud drive and choking things up. This would count for both deliberate and accidental drags.
That might make sense, but it’s not the only reason why the exclusion list exists in the first place. As you know, one of the new iCloud features in iOS 13, iPadOS and macOS Catalina is the long-requested ability to share a whole iCloud Drive folder with one or more people, bringing iCloud Drive one step closer to becoming a fully viable replacement for Dropbox.
Now, I wonder if I can put an “iCloud Drive” folder in my “Dropbox” folder…