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TNCS-0004 - Handling Conflict Errors in ChronoSync

February 14, 2014


Conflicts arise in bi-directional syncs only. It is simply a file or folder that has changed in some way since the last synchronization. This change may be one of the dates, file size, or another file attribute.

Since both files have changed, ChronoSync wants to make sure the correct file is copied so an error is created. If a scheduled Synchronization is run an error is posted to the sync document Log. If you run the Synchronization manually, an error message will be presented during the sync and you can then choose the file you want to use. If you are not sure of what file to use then investigate both files then run a manual Synchronization and choose a file.

You can handle Conflicts automatically by going to the Options Panel under the 'Reporting and Error Handling' section. Click the popup menu next to 'Conflicts:' and select what you want ChronoSync to do when it encounters a Conflict.


'Attribute Conflicts' occur when a date or other file attribute appears to be out of sync. It doesn't affect the data in the file and is a quick item for ChronoSync to re-sync. The recommend setting of the 'Conflict:' popup menu is 'User Newer'.

To troubleshoot this issue, you might want to verify that the two targets in your sync document are syncing to the same time server automatically so dates and times are accurate on all Macs.

Also, some applications play havoc with dates. We have seen MS Office applications update creation and modification dates unexpectedly. So maybe an application you are using is triggering the date change. Try to pay attention to the files that generate a conflict and then try to figure out what you used to last modify or view the file.


Many times, accessing a folder, or spotlight indexing can result in a change to its modification date. This triggers the conflict. The recommend setting of the 'Conflict:' popup menu is 'Copy'.

Since a large number of Folder Conflicts can make it easy to miss conflicts on legitimate files, you can use this technique to synchronize and resolve all folder conflicts before syncing the actual files.

This technique involves setting up a second sync document for the same two targets. In the new sync document, create a Simple rule to skip all files. Something like "File size is less than zero" should eliminate all files.

Make sure deletions aren't synchronized, just to be safe. On the Options Panel, in the 'Reporting & Error Handling' section, set the 'Conflicts:' popup menu to "Use Newer". That should take care of all folders.

Run the new sync document first, then run your regular sync document afterwards. Add them both to a container, if you want to run/schedule them as a single entity.


Feb-12-2014 - Created from Internal Support Notes.