I've got the same problem here. DS713+ running DSM 5.2-5655 Update 2 and Sync 2.0.120-1. DS713+ is Cedarview. I am running the free version currently. I was previously using 1.4 successfully for many months and it worked flawlessly. I then uninstalled and installed version 2 but left the 1.4 folders in place. The sync worked perfectly. I then didn't like the idea of them being 1.4 folders, thinking I was missing out on something, so removed them, and added 2.0 folders. The PC immediately, quickly indexed 154GB of data on one of the folders correctly. The NAS started indexing its folders and for the 154GB folder got up to about 745MB and stopped for days .... so I disconnected and removed the share, then removed the .sync hidden folder on the NAS drive and added the folder again ... and it's got up to 35MB and won't index any more. I've logged a ticket with support who I am now awaiting a further response to their request for debug log files. I'm thinking I may go back to 1.4 on the PC as it seems this could solve things.