calendar API no longer works after update

Currently reading
calendar API no longer works after update

Operating system
  1. macOS
  2. Windows
Mobile operating system
  1. iOS
I am dealing with the same issue.
Did you get it solved? If so, would you post an update here?

I did a bunch of debugging, up to a point where it all seems a shot in the dark.
Unfortunately Synology-Support is not helpful either.
Some more info on the error codes for the Synology Calendar API:

I found the required parameters. Take a special note of the last two, they need a value with at least an empty array [ ].
And dtstart and dtend now need a timestamp.

api: SYNO.Cal.Event
method: create
version: 5
cal_id: "/SomeUser/sdfghjkl/"
original_cal_id: "/SomeUser/sdfghjkl/"
summary: "test"
is_all_day: false
tz_id: "Europe/Amsterdam"
dtstart: 1715583600
dtend: 1715587200
is_repeat_evt: false
color: ""
description: ""
participant: []
notify_setting: []
Calendar issues reported recently by Community users...

I suggest you open a support ticket.
With the new parameters and dtstart and dtend as timestamp it works fine. But with the method „set“ always the error 9009 comes up. Any ideas ?
Last edited:
Yes I figured it out.

For set you'll need at least the parameters below.
It's required to add the current dav_etag, which you first must retrieve via get.

api: SYNO.Cal.Event
method: set
version: 5
evt_id: 102293
cal_id: "/User/xntphmr/"
original_cal_id: "/User/xntphmr/"
summary: "Some summary"
color: ""
description: ""
dav_etag: "aqveyjqyewhpecenzujahpjipqcjvhqr"
is_all_day: false
tz_id: "Europe/Amsterdam"
dtstart: 1716188400
dtend: 1716192000
is_repeat_evt: false
repeat_setting: null
participant: []
notify_setting: []
location_info: {"address":"","gps":{"lat":-1,"lng":-1},"map_type":"","name":"","place_id":""}
attachments: []

The trick is to inspect your browser's network traffic while using the Calendar-browser-app (Synology Calendar GUI).

Create an account or login to comment

You must be a member in order to leave a comment

Create account

Create an account on our community. It's easy!

Log in

Already have an account? Log in here.

Welcome to! is an unofficial Synology forum for NAS owners and enthusiasts.

Registration is free, easy and fast!