Smart Synchronization

The smart synchronization connect mode allows working with files when offline. You can also choose to make explicitly all or only selected files and folders available for offline use. Changes to files are saved in a local cache first and uploaded in the background as soon as a connection is available.

Status of Files 

Files and folders on a mounted volume have a status icon overlay in File Explorer (Windows) and Finder (macOS).

Note

Please make sure to enable the Mountain Duck Integration in System Preferences → Extensions → Finder on macOS.

Up to Date 

The file or the contents of a directory has been opened and downloaded to your computer and therefore currently synced with the server or cloud storage. The file takes disk space on your computer and can always be opened even when no connection to the server or cloud storage is possible. New files in a directory on the remote server will appear as Online Only and are not downloaded automatically. Files copied to a volume are kept cached by default.

Note

Files can be purged automatically from the cache when not accessed or the cache size limit is exceeded. Refer to Cache Limitations.

In Sync 

The file or directory is selected to be synced with the server or cloud storage to always keep offline. The file takes disk space on your computer and can always be opened even when no connection to the server or cloud storage is possible. New files in a directory on the remote server will be downloaded automatically.

Tip

Files explicitly selected to keep offline are not automatically purged. Refer to Cache Limitations.

Online Only 

The file can only be opened when a connection to the server or cloud storage can be made. The file does not take any space on your computer. The file is downloaded on demand when you open it.

Sync in Progress 

The file or directory is currently syncing with the server or cloud storage. Check the menu with the sync status for current download or upload progress.

Sync Error 

There was an error updating the file after changes. You are missing permission to write to the file or another problem occured. Please contact your web hosting service provider for assistance. To resolve the error, move the file to your local disk, and reload the directory or use the Retry option within the context menu. Refer to Sync Conflicts for possible error scenarios.

Ignored 

The file is only saved in a local temporary location and never synced to the server or cloud storage.

Tip

Rename a file to synchronize with the server.

Context Menu Options 

Refer to Context Menu in Finder and Windows File Explorer.

Keep Offline 

Choose Mountain Duck → Keep Offline on Local Disk to make files and folders available offline. The status of the file will change to In Sync. The action is recursive for all contained files when a folder is selected and applies to new files found on the remote storage.

Note

As long as the volume is mounted, files marked Up to Date or In Sync with a green checkmark remain accessible even if the network connection drops. Changes are synchronized in the background when the server is reachable again. This is made possible by caching file contents in an obfuscated cache on a local disk, which is unavailable for direct use.

To reach the context menu right-click on a file or folder in File Explorer (Windows) or Finder (macOS). Refer to Finder Extension & Windows File Explorer Extension.

Delete on Local Disk 

Choose Mountain Duck → Delete on Local Disk to delete the offline copy. The status of the file will change to Online Only. The action is recursive for all contained files when a folder is selected and allows you to quickly free up space used in the cache on your local disk.

Note

Files will get cached again regardless this setting if accessed again later (e.g. Finder and Windows Explorer thumbnail preview and media file metadata retrieval).

Cache Size 

The cache size can be limited per bookmark within the Preferences → Sync tab. Also files not accessed within a chosen period of time can be purged. Refer to Cache Limitations.

Sync Conflicts 

A conflict may be caused by two or more users editing the same files at the same time or while on the road before the files are synced. We do not merge changes to files like version control systems do. The file with conflicting edits will be renamed with the current time added to the filename. You will have to compare the changes manually and delete the duplicate file afterwards.

Action	Error Cause	Error State (Overlay Icon)	Remarks	Manual Conflict Resolution
Indexing folder	Missing permission	Sync Error for files with pending write	Other files are removed from local cache	Context menu with options Retry
Open placeholder (1) file	Permission failure reading file on server	-	Status remains Online	-
Select to keep file offline placeholder (1) file	Permission failure reading file on server	Sync Error	-	Context menu with options Retry
Indexing folder containing files in write error state	File with write sync error state not found on server	Sync Error	For error states caused by other Operations than `write`, the file is removed on local disk	Context menu with options Retry
Open placeholder (1) file	Directory index is out of sync. File not found on server	-	File is deleted in local cache	-
Edit file deleted on server	Directory index is out of sync. File not found on server	-	File is uploaded anew to server	-
Edit file renamed on server	Directory index is out of sync. File not found on server	-	File is uploaded anew to server	-
Edit file already changed on server	Last seen checksum differs from current checksum on server. (Or timestamp when server does not offer checksum verification)	-	Existing file on server is renamed to `<filename> timestamp.<extension>`. Eventually with user preference to default to sync error instead.	User has to manually merge the conflicting edits.
Edit file with parent folder missing on server	Upload fails because parent folder is not found on server	Sync Error	-	Move file to different folder or Retry option in context menu
Move or rename file to target that already exists on server	Directory index is out of sync	-	Existing file on server is renamed to `<filename> timestamp.<extension>`. Eventually with user preference to default to sync error instead.	User has to manually merge the conflicting edits.
Move or rename directory to target that already exists on server	Directory index is out of sync	-	Existing directory on server is renamed to `<folder> timestamp.<extension>`	User has to manually merge the conflicting edits.
Move or rename directory that no longer exists on server	Directory index is out of sync	Sync Error	Directory is removed from local cache	-
Create file that exists already on server	Directory index is out of sync	-	Failure creating file is ignored	-
Create folder that exists already on server	Directory index is out of sync	-	Failure creating folder is ignored	-
Deleting file already changed on server	Directory index is out of sync	-	File is deleted on server	-

(1) Indexed file in local cache not downloaded from server

Sync Progress 

Changes to files are uploaded in the background as soon as a connection is available. Progress is reported by animating the status bar icon and a menu item titled Sync in Progress.

Detailed status for current transfers is available in the Sync submenu. Refer to Sync Progress.

Pause Sync 

You can manually pause background syncing by selecting Pause Sync in the submenu for the sync status. Syncing is also paused automatically when your network connection to the server is interrupted but resumed automatically when a connection is restored.

Warning

When synchronization is paused by selecting Pause Sync in the menu or caused by a connectivity problem, no changes from the server will be detected.

The paused sync status is indicated with a greyed-out icon in the tray (Windows) or status bar (macOS).

Cancel upload in progress 

To abort the upload of a file, follow these steps:

Choose Pause Synchronization in the Mountain Duck Synchronization menu.
Delete the file
Resume Synchronization in the dropdown menu.

You can use the steps as well to cancel Keep Offline processes.

Cancel download in progress 

To abort the download of a file, follow these steps:

Choose Pause Synchronization in the Mountain Duck Synchronization menu.
Select Delete on local Disk within the Mountain Duck context menu.
Resume Synchronization in the dropdown menu.

Sync Errors 

Files that failed to sync get a sync error badge. You can try to repeat the failed transfer by selecting Mountain Duck → Retry in the context menu.

Resolve Errors 

If a sync error cannot be solved using Mountain Duck → Retry because the server does not allow the operation (i.e. due to a permission issue), you can resolve the error state on the file or folder by

Move the file or folder to another location on the volume
Delete the file or folder

To upload files to a target directory no longer existing on the server, you have to move the files to a location found on the server.

File History 

You can lookup the latest changes to files. Refer to Recent Files

Notifications 

File Added: New file found on server for previously indexed folder.
File Updated: File changed on server since previously indexing a folder
Sync Conflict: Conflicting change in file lead to duplicate of file being created with previous content edited on server.

You can adjust which notifications you want to receive within Preferences → Notifications.

Preferences 

Refer to Preferences.