# Make Nextcloud, Collabora work with Traefik 3.6.4 **URL:** \ **Category:** ℹ️ Support\ **Tags:** nc32, docker, office, files, collabora-online, nextcloud-office, traefik\ **Created:** [December 11, 2025, 7:53pm UTC](https://help.nextcloud.com/t/make-nextcloud-collabora-work-with-traefik-3-6-4/237255 "2025-12-11T19:53:54Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![mklemme](https://help.nextcloud.com/letter_avatar/mklemme/32/5_5575768a8748004e209b776fc1b2916d.png) [@mklemme](https://help.nextcloud.com/u/mklemme)\ **Post date:** [December 11, 2025, 7:53pm UTC](https://help.nextcloud.com/t/make-nextcloud-collabora-work-with-traefik-3-6-4/237255/1 "2025-12-11T19:53:55Z")
> **Support intro** > > ## Sorry to hear you’re facing problems. 🙁 > > _The community help forum ([help.nextcloud.com](http://help.nextcloud.com)) is for home and non-enterprise users. Support is provided by other community members on a best effort / “as available” basis. All of those responding are **volunteering their time to help you.** _ > > **If you’re using Nextcloud in a business/critical setting, paid and SLA-based support services can be accessed via [portal.nextcloud.com](http://portal.nextcloud.com) where Nextcloud engineers can help ensure your business keeps running smoothly.** > > ## Getting help > > In order to help you as efficiently (and quickly!) as possible, please fill in as much of the below requested information as you can. > > **Before clicking submit** : Please check if your query is already addressed via the following resources: > > - [Official documentation](https://docs.nextcloud.com) (searchable and regularly updated) > - [How to topics and FAQs](https://help.nextcloud.com/c/how-to-faqs/9) > - [Forum search](https://help.nextcloud.com/search) > > (Utilizing these existing resources is typically faster. It also helps reduce the load on our generous volunteers while elevating the signal to noise ratio of the forums otherwise arising from the same queries being posted repeatedly). Some or all of the below information will be requested if it isn’t supplied; for fastest response please provide as much as you can. ❤ ## The Basics - Nextcloud Server version _(e.g., 29.x.x)_: - `32.0.2, 31.0.x` - Operating system and version _(e.g., Ubuntu 24.04)_: - _Ubuntu 24.04_ - Web server and version _(e.g, Apache 2.4.25)_: \* - Reverse proxy and version \_(e.g. nginx 1.27.2) - `Traefik 3.6.4` - When did this problem seem to first start? - `When updating to Traefik 3.6.4` - Installation method _(e.g. AlO, NCP, Bare Metal/Archive, etc.)_ - `Docker ` - Are you using CloudfIare, mod\_security, or similar? _(Yes / No)_ - `no` ### Summary of the issue you are facing: When updating Traefik to 3.6.4, I saw when opening a document in Nextcloud office > \*Laden des Dokuments fehlgeschlagen. > > Socket-Verbindung konnte nicht hergestellt werden oder Socket-Verbindung wurde unerwartet geschlossen. Der Reverse-Proxy ist möglicherweise falsch konfiguriert. Bitte wenden Sie sich an den Administrator. Weitere Informationen zur Proxy-Konfiguration finden Sie unter [https://sdk.collaboraonline.com/docs/installation/Proxy\_settings.html](https://sdk.collaboraonline.com/docs/installation/Proxy_settings.html)\* > > Failed to load the document. > > Could not establish a socket connection, or the socket connection was unexpectedly closed. The reverse proxy may be configured incorrectly. Please contact your administrator. For more information on proxy configuration, see [https://sdk.collaboraonline.com/docs/installation/Proxy\_settings.html](https://sdk.collaboraonline.com/docs/installation/Proxy_settings.html). I found a lot of _Error 400_ messages in the browser networking console. After a lot of searching I found out that the Traefik update was to blame. A downgrade fixed it. After more searching I found [Traefik Migration Documentation - Traefik](https://doc.traefik.io/traefik/migrate/v3/#v364) , and how to fix it for the current and future versions. I needed to add the following `encodedCharacters` blocks to my `traefik.yml`: ```yaml entryPoints: http: address: ":80" https: address: ":443" http: encodedCharacters: allowEncodedSlash: true allowEncodedBackSlash: true allowEncodedNullCharacter: false allowEncodedSemicolon: false allowEncodedPercent: true allowEncodedQuestionMark: true allowEncodedHash: false ``` The problem is solved. This is more meant as a how-to. ---
**Author:** ![mklemme](https://help.nextcloud.com/letter_avatar/mklemme/32/5_5575768a8748004e209b776fc1b2916d.png) [@mklemme](https://help.nextcloud.com/u/mklemme)\ **Post date:** [December 12, 2025, 5:08pm UTC](https://help.nextcloud.com/t/make-nextcloud-collabora-work-with-traefik-3-6-4/237255/2 "2025-12-12T17:08:39Z")
Oh, it turned out that the filter of the user list by group was also throwing Error 400 when clicking a group. I have modified my post above. ---
**Author:** ![doc75](https://help.nextcloud.com/letter_avatar/doc75/32/5_5575768a8748004e209b776fc1b2916d.png) [@doc75](https://help.nextcloud.com/u/doc75)\ **Post date:** [December 14, 2025, 10:01am UTC](https://help.nextcloud.com/t/make-nextcloud-collabora-work-with-traefik-3-6-4/237255/3 "2025-12-14T10:01:29Z")
Thanks @mklemme. I had the same issue and your solution works perfectly. I just removed the lines with `false` as this is their default value. ---
**Author:** ![pip](https://help.nextcloud.com/user_avatar/help.nextcloud.com/pip/32/76033_2.png) [@pip](https://help.nextcloud.com/u/pip)\ **Post date:** [December 15, 2025, 1:48am UTC](https://help.nextcloud.com/t/make-nextcloud-collabora-work-with-traefik-3-6-4/237255/4 "2025-12-15T01:48:11Z")
I played around hours in traefik settings. This fixed the issue, thank you soo much ---
**Author:** ![Sebbroe](https://help.nextcloud.com/letter_avatar/sebbroe/32/5_5575768a8748004e209b776fc1b2916d.png) [@Sebbroe](https://help.nextcloud.com/u/Sebbroe)\ **Post date:** [December 27, 2025, 1:16pm UTC](https://help.nextcloud.com/t/make-nextcloud-collabora-work-with-traefik-3-6-4/237255/5 "2025-12-27T13:16:05Z")
Same here. thx for the solution! ---
**Author:** ![wwe](https://help.nextcloud.com/user_avatar/help.nextcloud.com/wwe/32/72963_2.png) [@wwe](https://help.nextcloud.com/u/wwe)\ **Post date:** [January 9, 2026, 10:19pm UTC](https://help.nextcloud.com/t/make-nextcloud-collabora-work-with-traefik-3-6-4/237255/6 "2026-01-09T22:19:21Z")
many thanks for the write-up. I hit the issue with core #files app navigating a folder with `#` in the name. Nextcloud complained the folder doesn’t exists and I was already 😰 as it was a folder with my family pictures archive - but fortunately I remember this discussion and also the traefik github discussions.. tldr 1. if you have folders with `#` in the name 2. use ```auto #endpoint name web-secure: encodedCharacters: allowEncodedHash: true ``` conclusion: at the end “_security improvement_” from upstream breaks lot of things ☹ ---
**Author:** ![system](https://help.nextcloud.com/user_avatar/help.nextcloud.com/system/32/29333_2.png) [@system](https://help.nextcloud.com/u/system)\ **Post date:** [April 9, 2026, 10:19pm UTC](https://help.nextcloud.com/t/make-nextcloud-collabora-work-with-traefik-3-6-4/237255/7 "2026-04-09T22:19:30Z")
This topic was automatically closed 90 days after the last reply. New replies are no longer allowed.