# Impossible to upgrade since 2.1.5

**URL:** https://forum.syncthing.net/t/impossible-to-upgrade-since-2-1-5/27197
**Category:** Support
**Created:** [October 8, 2026, 12:04am UTC](https://forum.syncthing.net/t/impossible-to-upgrade-since-2-1-5/27197 "2026-10-08T00:04:20Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![TigersWay](https://forum.syncthing.net/user_avatar/forum.syncthing.net/tigersway/32/5568_2.png) [@TigersWay](https://forum.syncthing.net/u/TigersWay)
#### Post date: [October 8, 2026, 12:04am UTC](https://forum.syncthing.net/t/impossible-to-upgrade-since-2-1-5/27197/1 "2026-10-08T00:04:20Z")

</div>

Hi, I have two syncthing instances - which have been working for years - on two different servers, which I tried to classically update, from 2.1.3 to 2.1.5 or 2.1.6. I was unable to access them.

- `systemctl status syncthing@syncthing` doesn’t give me anything wrong,
- they are behind caddy (2.11.4) with the usual

```plaintext
    reverse_proxy http://localhost:8384 {
      header_up Host {upstream_hostport}
    }
  }

```

- downgrading them to 2.1.3 is fine!

Any idea, any help would be welcome! Thanks