Why won't Dropbox sync particular files on my mac?

Question

I'm using dropbox across several machines - two macs, two linux machines.

All are working happily - except for one mac, where there are 4 files that persistently refuse to update.

In finder, these 4 files have a red X icon. The dropbox menu is stuck on 'syncing' (and has been for about a week now), and has part of an error message saying that it can't write to these files.

In Finder's "Get Info", it says I have read+write access; at the commandline, ls shows that they have -rwxrwxrwx permissions.

Answer 1

The HFS+ filesystem includes flags, which provide extra permissions on top of the usual Unix permissions. One of the flags is "unchangeable" - which does what the name suggests.

Several files inside my dropbox had been flagged as unchangeable. You can check for this with ls:

Sombrero:directory polleyj$ ls -Ol
total 0
-rwxrwxrwx  1 polleyj  admin  uchg 0 15 Jan 23:29 file1

-0 tells ls to show the extra flags; uchg indicates that this files in unchangeable.

Sombrero:directory polleyj$ rm file1 
override rwxrwxrwx  polleyj/admin uchg for file1? y
rm: file1: Operation not permitted
Sombrero:directory polleyj$ mv file1 ..
mv: rename file1 to ../file1: Operation not permitted
Sombrero:directory polleyj$ 

To fix this, use chflags:

Sombrero:directory polleyj$ chflags nouchg file1 
Sombrero:directory polleyj$ rm file1 
Sombrero:directory polleyj$ ls
Sombrero:directory polleyj$ 

Answer 2

I ran into the same problem and found out one of the directories in Dropbox was owned by a different user. Running chown on that directory cleared up the sync issue.

Answer 3

I found another hitch that prevents Dropbox from synchronizing specific files and folders, that isn't mentioned anywhere else: If you use certain special characters like for example backslash \ in the Dropbox folder or file name. See: Certain files won’t sync in Dropbox.

Answer 4

1) Your Dropbox is on a network share that is disconnecting and reconnecting (restarting may help) 2) You're over your quota. You should remove files (or upgrade :-).

Answer 5

I had a red cross icon next to a pdf someone else sent me. I saw it for about three days. What I did was copy the pdf in the Desktop, changing its name. In the pdf information, just in case, reduced my privileges to "read only". Then logged off from Dropbox in my three macs, and logged in to Dropbox via the internet. Then permanently deleted the reluctant pdf. Finally, logged in again my laptop to Dropbox, and copied the pdf, from the Desktop to the right Dropbox folder. The red cross disappeared. Now I have logged in to Dropbox via the desktop in my other computers and there are no more red crosses in that famous pdf. Hope it helps.

Answer 6

Sometimes you just need to wait. Go to the Dropbox icon in the menu bar and check the status ticker. It will tell you what it's doing. I had a video file with a red cross for about an hour while either Dropbox or El Capitan sorted something out preparing it for upload, then it just started of its own accord. An hour later (big file, s-l-o-w internet), it changed to the blue uploading icon, an hour and a half after that, to a green tick.