# Collabora on plesk with kolab premium mail **URL:** \ **Category:** Installation & Configuration\ **Created:** [November 13, 2025, 6:38pm UTC](https://forum.collaboraonline.com/t/collabora-on-plesk-with-kolab-premium-mail/4116 "2025-11-13T18:38:14Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![piticu81](https://avatars.discourse-cdn.com/v4/letter/p/8e8cbc/32.png) [@piticu81](https://forum.collaboraonline.com/u/piticu81)\ **Post date:** [November 13, 2025, 6:38pm UTC](https://forum.collaboraonline.com/t/collabora-on-plesk-with-kolab-premium-mail/4116/1 "2025-11-13T18:38:14Z")
hello i have tried to install collabora on plesk panel with premium mail but im get error | 6d6] | | | --- | --- | ```auto stderr: W: GPG error: https://collaboraoffice.com/repos/CollaboraOnline/23.05/customer-deb-Kolab-7537e68e8a07cf290a8c6cfcf4205db05b560582 ./ InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY D8915E456E7C440E E: The repository 'https://collaboraoffice.com/repos/CollaboraOnline/23.05/customer-deb-Kolab-7537e68e8a07cf290a8c6cfcf4205db05b560582 ./ InRelease' is not signed. ``` ```auto Error executing: ;'aptitude' '-d' '-y' 'install' 'collabora-online-brand' 'coolwsd'' Error executing: ;'aptitude' '-o Dpkg::Options::="--force-confold"' '-o Dpkg::Options::="--no-triggers"' '-y' 'install' 'collabora-online-brand' 'coolwsd'' Error executing: ;'aptitude' '-y' 'install' 'collaboraoffice-dict-de' 'collaboraofficebasis-de' 'collaboraoffice-dict-en' 'collaboraofficebasis-en-gb' 'collaboraoffice-dict-es' 'collaboraofficebasis-es' 'collaboraoffice-dict-fr' 'collaboraofficebasis-fr' 'collaboraoffice-dict-it' 'collaboraofficebasis-it' 'collaboraoffice-dict-nl' 'collaboraofficebasis-nl' 'collaboraoffice-dict-pt-br' 'collaboraofficebasis-pt-br' 'collaboraoffice-dict-pt-pt' 'collaboraofficebasis-pt' 'collaboraoffice-dict-ru' 'collaboraofficebasis-ru'' ``` ---
**Author:** ![darshan](https://dub1.discourse-cdn.com/flex013/user_avatar/forum.collaboraonline.com/darshan/32/2230_2.png) [@darshan](https://forum.collaboraonline.com/u/darshan)\ **Post date:** [November 14, 2025, 5:30am UTC](https://forum.collaboraonline.com/t/collabora-on-plesk-with-kolab-premium-mail/4116/2 "2025-11-14T05:30:40Z")
Hii @piticu81 You’re getting that error because the Collabora repository you added isn’t trusted yet, since the GPG signing key isn’t installed on your server. You need to import the missing key `D8915E456E7C440E` before Plesk (or apt/aptitude) can install Collabora. After that, the `aptitude install` command in Plesk should run without the NO\_PUBKEY error. If the repo URL came from Kolab’s Premium Mail integration, double-check their documentation, because sometimes they rotate customer-specific repo keys. Also, I noticed you’re installing Collabora Online 23.05, which is very outdated now. The current long-term supported version is **25.04** , so you should really switch to the newer repository — it has all the fixes, security updates and compatibility improvements. [https://www.collaboraonline.com/code/#learnmorecode](https://www.collaboraonline.com/code/#learnmorecode) Thanks Darshan ---
**Author:** ![piticu81](https://avatars.discourse-cdn.com/v4/letter/p/8e8cbc/32.png) [@piticu81](https://forum.collaboraonline.com/u/piticu81)\ **Post date:** [November 14, 2025, 6:51pm UTC](https://forum.collaboraonline.com/t/collabora-on-plesk-with-kolab-premium-mail/4116/3 "2025-11-14T18:51:14Z")
I have installed the collabora from plesk market place i dont know how make it work or how i can fix that issue ---
**Author:** ![darshan](https://dub1.discourse-cdn.com/flex013/user_avatar/forum.collaboraonline.com/darshan/32/2230_2.png) [@darshan](https://forum.collaboraonline.com/u/darshan)\ **Post date:** [December 2, 2025, 5:31am UTC](https://forum.collaboraonline.com/t/collabora-on-plesk-with-kolab-premium-mail/4116/4 "2025-12-02T05:31:23Z")
You only need to import the missing key once. Connect to your server (SSH) and run: ```auto sudo gpg --keyserver keyserver.ubuntu.com --recv-keys D8915E456E7C440E sudo gpg --export D8915E456E7C440E | sudo tee /etc/apt/trusted.gpg.d/collabora.gpg >/dev/null sudo apt update ``` After this, go back to **Plesk → Extensions → Collabora Online** and press **Install** again. It should work now. ---
**Author:** ![piticu81](https://avatars.discourse-cdn.com/v4/letter/p/8e8cbc/32.png) [@piticu81](https://forum.collaboraonline.com/u/piticu81)\ **Post date:** [December 2, 2025, 11:27am UTC](https://forum.collaboraonline.com/t/collabora-on-plesk-with-kolab-premium-mail/4116/5 "2025-12-02T11:27:15Z")
E: The repository ‘[https://www.collaboraoffice.com/repos/CollaboraOnline/23.05/customer-deb-](https://www.collaboraoffice.com/repos/CollaboraOnline/23.05/customer-deb-) ./ Release’ does not have a Release file. N: Updating from such a repository can’t be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. root@wizardly-lovelace:/home/ubuntu# E: The repository ‘[https://www.collaboraoffice.com/repos/CollaboraOnline/23.05/customer-deb-](https://www.collaboraoffice.com/repos/CollaboraOnline/23.05/customer-deb-) ./ Release’ does not have a Release file. N: Updating from such a repository can’t be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details ---
**Author:** ![darshan](https://dub1.discourse-cdn.com/flex013/user_avatar/forum.collaboraonline.com/darshan/32/2230_2.png) [@darshan](https://forum.collaboraonline.com/u/darshan)\ **Post date:** [December 2, 2025, 2:38pm UTC](https://forum.collaboraonline.com/t/collabora-on-plesk-with-kolab-premium-mail/4116/6 "2025-12-02T14:38:53Z")
This error happens because the APT source you added is **wrong or malformed** , specifically the part: ```auto https://www.collaboraoffice.com/repos/CollaboraOnline/23.05/customer-deb- ./ ``` The `customer-deb- ./` part is invalid, so APT looks for a **Release file** in a non-existent path. ### Why this happens Collabora’s enterprise repositories require **exact customer repository URLs** , and they never end with `customer-deb- ./`. It means the repo entry was incorrectly copied or a variable didn’t expand. * * * ### 1. Open the repo file Check what you added under `/etc/apt/sources.list` or `/etc/apt/sources.list.d/*.list`: ```bash sudo nano /etc/apt/sources.list.d/collabora.list ``` ### 2. Remove the broken line Delete any line that looks like: ```auto deb https://www.collaboraoffice.com/repos/CollaboraOnline/23.05/customer-deb- ./ ``` ### 3. Add the correct Collabora CODE repo (if your intention was to install CODE) For Debian/Ubuntu: ```bash echo "deb https://collaboraoffice.com/repos/CollaboraOnline/CODE-deb/ /" | sudo tee /etc/apt/sources.list.d/collabora-online-code.list ``` Install key: ```bash sudo wget https://collaboraoffice.com/repos/CollaboraOnline/CODE-deb/Release.key -O /usr/share/keyrings/collabora-code.gpg ``` Then: ```bash sudo apt update ``` * * * ## If you intended to use the **customer** (enterprise) repository You need the **exact URL** from your Collabora subscription email or customer portal. It will look like: ```auto https://www.collaboraoffice.com/repos/CollaboraOnline/23.05/customer-deb-/ ``` Not this: ```auto customer-deb- ./ ``` If you don’t have a customer ID, you cannot access the paid repository. ---
**Author:** ![piticu81](https://avatars.discourse-cdn.com/v4/letter/p/8e8cbc/32.png) [@piticu81](https://forum.collaboraonline.com/u/piticu81)\ **Post date:** [December 2, 2025, 5:33pm UTC](https://forum.collaboraonline.com/t/collabora-on-plesk-with-kolab-premium-mail/4116/7 "2025-12-02T17:33:54Z")
sudo wget /repos/CollaboraOnline/CODE-deb/Release.key -O /usr/share/keyrings/collabora-code.gpg HTTP request sent, awaiting response… 301 Moved Permanently Location: /repos/CollaboraOnline/CODE-deb/Release.key [following] –2025-12-02 17:26:54-- [https://www.collaboraoffice.com/repos/CollaboraOnline/CODE-deb/[Release.key](https://www.collaboraoffice.com/repos/CollaboraOnline/CODE-deb/Release.key)](https://www.collaboraoffice.com/repos/CollaboraOnline/CODE-deb/%5BRelease.key%5D(https://www.collaboraoffice.com/repos/CollaboraOnline/CODE-deb/Release.key)) Resolving ([www.collaboraoffice.com](http://www.collaboraoffice.com))… 157.90.115.48, 2a01:4f8:1c1e:efee::1 Connecting to www.collaboraoffice.com|157.90.115.48|:443… connected. HTTP request sent, awaiting response… 404 Not Found 2025-12-02 17:26:55 ERROR 404: Not Found. ---
**Author:** ![system](https://europe1.discourse-cdn.com/flex013/uploads/collaboraonline/original/1X/326930fc3c4344f7b3daaa009c34a90206dee4be.png) [@system](https://forum.collaboraonline.com/u/system)\ **Post date:** [January 1, 2026, 5:34pm UTC](https://forum.collaboraonline.com/t/collabora-on-plesk-with-kolab-premium-mail/4116/8 "2026-01-01T17:34:47Z")
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