Collabora on plesk with kolab premium mail

Installation & Configuration
1

hello i have tried to install collabora on plesk panel with premium mail but im get error

6d6] 
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.

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''
Collabora Online Weekly Meeting #242
2

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Also, I noticed you’re installing Collabora Online 23.05, which is very outdated now.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

Thanks
Darshan

3

I have installed the collabora from plesk market place i dont know how make it work or how i can fix that issue

4

You only need to import the missing key once.
Connect to your server (SSH) and run:

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.

5

E: The repository ‘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- ./ 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

6

This error happens because the APT source you added is wrong or malformed, specifically the part:

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:

sudo nano /etc/apt/sources.list.d/collabora.list

2. Remove the broken line

Delete any line that looks like:

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:

echo "deb https://collaboraoffice.com/repos/CollaboraOnline/CODE-deb/ /" | sudo tee /etc/apt/sources.list.d/collabora-online-code.list

Install key:

sudo wget https://collaboraoffice.com/repos/CollaboraOnline/CODE-deb/Release.key -O /usr/share/keyrings/collabora-code.gpg

Then:

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:

https://www.collaboraoffice.com/repos/CollaboraOnline/23.05/customer-deb-<your-customer-id>/

Not this:

customer-deb- ./

If you don’t have a customer ID, you cannot access the paid repository.

7

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)
Resolving (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.