[Solved] Btsync 1.3.105: Failed To Parse Folder Config. Error: Lexical Error: Invalid Char In Json Text

Recommended Posts


After updating to version 1.3.105 I get this error message in the logs.

Failed to parse folder config. Error: lexical error: invalid char in json text.                                        <!DOCTYPE html PUBLIC "-//W3C/                     (right here) ------^


Share this post

Link to post
Share on other sites



The problem is there. I have checked and I have no such header. I have the same configuration file on both my NAS.

{  "device_name" : "NAME",  "listening_port" : 7777,  "storage_path" : "/c/btsync",  "pid_file" : "/c/btsync/",  "check_for_updates" : true,  "disk_low_priority" : false,  "folder_rescan_interval" : 1500,  "use_upnp" : false,  "log_size" : 10,  "download_limit" : 0,  "upload_limit" : 0,  "webui" :  {    "listen" : "",    "login" : "admin",    "password" : "password"  }}

Share this post

Link to post
Share on other sites



This error looks to be bound to the fact that you've got a corrupt sync.conf file (which is stored at - it is also made of JSON format. 1.2 did not require this file to operate, while 1.3 does. Could you please check:


1. If you can download it directly with browser

2. If your PC is configured to use proxy server?

Share this post

Link to post
Share on other sites

Sync uses next ports and protocols to function:

  • Discovery of tracker and relay IPs:
    HTTP port 80 to (via DNS name) (
  • Connecting to the tracker server for automatic peer discovery:
    TCP and UDP port 3000 to (via direct IP,,,
  • Connecting to relay server to transfer data if direct connection is not possible:
    TCP and UDP port 3000 to (via direct IP,,
  • Direct connection to transfer data:
    TCP and UDP port <configured_by_user> to remote peer
  • Peers discovery in LAN
    Multicast UDP over port 3838
  • Automatic ports mapping over UPnP and NAT-PMP
    UDP multicast to port 1900
    UDP unicast to default gateway port 5351

Share this post

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.