There are two recommended solutions, depending on how widespread the synchronize problems are.
Only a few files have synchronization problems
If only a few of your files are having synchronize problems, try deleting the specifc dwsync.xml files, instead of recreating all of the synchronization information for your site.
1. Close Dreamweaver.
2. In Windows or Mac Finder, browse to your site's local root folder and browse to the folder that contains the files that are having synchronization problems. For each folder(s) having synchronization problems, locate the _notes folder and delete the dwsync.xml file inside of it. The dwsync.xml files only reside locally. Dreamweaver will never upload the dwsync.xml files to the server, and there is no reason to upload them to the server.
3. Re-open Dreamweaver and see if the problem is resolved.
Several or all files have synchronization problems
If you are experiencing widespread synchronization problems, then it is recommended to temporarily disable the "Maintain synchronization information" setting so that Dreamweaver recreates all of the synchronization information for your site.
1. Temporarily disable the "Maintain synchronization information" option from the Remote Info category of the advanced view of the Site Definition dialog box. This will delete all of the existing dwsync.xml files.
2. Close Dreamweaver.
3. Verify that all of the dwsync.xml files have been deleted from your local root folder and all of its subfolders. The dwsync.xml files are located in the _notes folder which are hidden by default in Dreamweaver, so check for the _notes folders and dwsync.xml files in the Windows or Macintosh file browsers. The dwsync.xml files only reside locally. Dreamweaver will never upload the dwsync.xml files to the server, and there is no reason to upload them to the server.
4. Re-open Dreamweaver and go into the site definition dialog box. Turn "Maintain synchronization information" back on. Dreamweaver will now recreate the dwsync.xml files as you transfer files back-and-forth to and from the server. See if the problem is resolved.