Couldn't start Dropbox - macOS Monterey 12.6.1

[jacherian]

My Dropbox (currently at 159.4.5870) stopped syncing on Friday (Status shows "Can't sync") showing an error as it launches when my user account logs in. "Couldn't start Dropbox. This is usually because of a permissions error. Storing your home folder on a network share can also cause an error. For more information, cick the help button below. My mac recently updated to 12.6.1 and that's when I noticed the problem. This issue did happen before when I was at 12.6.0 and then I did an advanced reinstall and the problem went away even after I updated Dropbox to the version where it now stores its cache in ~/Library/CloudStorage/Dropbox instead of the Dropbox folder under the user's home folder. I have already set the Full Disk Access permission for Dropbox in System Preferences, even before I had this issue pop up last week.

This is similar to last week's issue with eli1020 but they had more to report in the end of the dropbox_error...txt file than I do. The last line of my error file is:

dropbox.sync_engine.nucleus.thin_client.exceptions.NucleusConnectionTimeoutError: Nucleus clients are not running. Connection error: None

Here is my complete error log (redacted):

bn.BUILD_KEY: Dropbox
bn.VERSION: 159.4.5870
bn.constants.WINDOWS_SHELL_EXT_VERSION: 55
bn.is_frozen: True
machine_id: 82c1d10f-c70e-5faa-b374-9bfda866e62e
pid: 831
ppid: 1
uid: 502
user_info: pwd.struct_passwd(pw_name='jch****', pw_passwd='********', pw_uid=502, pw_gid=20, pw_gecos='Jch****', pw_dir='/Users/jch****', pw_shell='/bin/zsh')
effective_user_info: pwd.struct_passwd(pw_name='jch****', pw_passwd='********', pw_uid=502, pw_gid=20, pw_gecos='J****', pw_dir='/Users/jch****', pw_shell='/bin/zsh')
euid: 502
gid: 20
egid: 20
group_info: grp.struct_group(gr_name='staff', gr_passwd='*', gr_gid=20, gr_mem=['root', 'admin', 'jch****'])
effective_group_info: grp.struct_group(gr_name='staff', gr_passwd='*', gr_gid=20, gr_mem=['root', 'admin', 'jch****'])
DYLD_LIBRARY_PATH: None
cwd: '/'
real_path='/'
mode=0o40755 uid=0 gid=0
parent mode=0o40755 uid=0 gid=0
HOME: '/Users/jch****'
appdata: '/Users/jch****/.dropbox/instance1'
real_path='/Users/jch****/.dropbox/instance1'
mode=0o40700 uid=502 gid=20
parent mode=0o40755 uid=502 gid=20
dropbox_path: '/Users/jch****/Library/CloudStorage/Dropbox'
real_path='/Users/jch****/Library/CloudStorage/Dropbox'
mode=0o40700 uid=502 gid=20
parent mode=0o40755 uid=502 gid=20
sys_executable: '/Applications/Dropbox.app/Contents/MacOS/Dropbox'
real_path='/Applications/Dropbox.app/Contents/MacOS/Dropbox'
mode=0o100755 uid=501 gid=20
parent mode=0o40755 uid=501 gid=20
trace.__file__: '/Applications/Dropbox.app/Contents/Resources/python-packages.zip/dropbox/client/ui/common/boot_error.pyc'
real_path='/Applications/Dropbox.app/Contents/Resources/python-packages.zip/dropbox/client/ui/common/boot_error.pyc'
not found
parent not found
tempdir: '/var/folders/p5/g3dq42dj7pq92fld_77hgp1h0000gp/T'
real_path='/private/var/folders/p5/g3dq42dj7pq92fld_77hgp1h0000gp/T'
mode=0o40700 uid=502 gid=20
parent mode=0o40755 uid=502 gid=20
Traceback (most recent call last):
File "dropbox/client/main.pyc", line 810, in wrapper
File "dropbox/client/main.pyc", line 6423, in finish_dropbox_boot
File "dropbox/client/message_queue.pyc", line 305, in _wrapped
File "dropbox/client/main.pyc", line 5948, in _init_components_for_account
File "dropbox/client/main.pyc", line 5872, in create_sync_engine
File "dropbox/sync_engine_boundary/factory.pyc", line 225, in make_sync_engine
File "dropbox/sync_engine/nucleus/classic_client/sync_engine.pyc", line 244, in __init__
File "dropbox/sync_engine/nucleus/classic_client/modern_client/modern_client.pyc", line 322, in __init__
File "dropbox/client/gandalf/legacy.pyc", line 296, in add_on_changed_callback
File "dropbox/sync_engine/nucleus/classic_client/modern_client/modern_client.pyc", line 475, in _update_feature_configs
File "dropbox/sync_engine/nucleus/classic_client/modern_client/modern_thin_client.pyc", line 286, in UpdateFeatureConfigForFswRules
File "dropbox/sync_engine/nucleus/thin_client/fp_client.pyc", line 236, in __getattr__
dropbox.sync_engine.nucleus.thin_client.exceptions.NucleusConnectionTimeoutError: Nucleus clients are not running. Connection error: None

[Jay]

Hi @jacherian, thanks for bringing this to our attention.

Just for clarification, have you already performed an advanced reinstallation when you experienced this issue on your device?

This will help me to assist further!

[jacherian]

Hi Jay,

Yes, when it stopped working last time (around early Oct), I did an advanced reinstall and then Dropbox seemed to work.
Fortunately for me (but unfortunately for this support forum post), my Dropbox seems to have auto-updated to 160.4.4703 this morning, and now Dropbox opens on user login and is able to sync now.

[Jay]

I'm glad to hear that the issue appears to be resolved now.  If you need any further assistance in the future, please let me know.

Enjoy the rest of your week!

[jacherian]

Unfortunately (for me), the Dropbox (160.4.4703) has stopped working again. When it launches, it shows: "Dropbox unexpectedly quit. Your files are safe. Restart Dropbox to resume sync and other features. <Restart Dropbox> <Close>" And the Dropbox menu shows "Can't sync". Any ideas other than an advanced reinstall ?

[Walter]

Hey @jacherian, sorry to hear about this.

Would it be OK if we reach out via email to have a further look internally? 

[jacherian]

Yes, you can reach me via email.

[MelissaBecker]

Hi Jay,

Yes, I did an advanced reinstall when Dropbox stopped operating the last time (in early October).
Thankfully (though regrettably for this support forum post), Dropbox seems to have auto-updated to version 160.4.4703 this morning, and Dropbox is now opening on user login and syncing correctly. drift boss

[Walter]

Sure thing @jacherian - you've got  

[jacherian · Accepted solution]

My Dropbox autoupdated (via Dropbox Update process) to 161.4.4923 (released Nov 9, 2022 ) and Dropbox no longer has an issue starting up and my files  are up to date. @Walter pointed me to 161.4.4923 stable build and the offline installer updated the /Applications/Dropbox app as well.  See all the desktop builds by going to dropboxforum.co, under the "Do More with Dropbox" > "Desktop client builds" menu at the top of the website.