Issue Plesk Premium eMail Webmail does not work anymore

[onki]

Server operating system version

ubuntu 24.4.

Plesk version and microupdate number

18.0.76 build1800260417

Since the last Plesk update the Plesk Webmail does not work correctly.
The mails are listed but no mail can be previewed or opened.
According to my hoster (Hosteurope) this is related to a PHP version compatibility problem (PHP 8.4)
There are some compatible Kolab PHP packages missing.

Please fix that asap as calendar and contact syncronisation as well as the webmeil interface do not work.

Thanks
Onki

 

[Sebahat.hadzhi]

Hello, Onki. The "Plesk Premium Email, powered by Kolab" requires PHP 8.2. At this point, support for PHP 8.4 has not been officially introduced. Do you have PHP 8.2 installed on the system? If it has been removed, please add it from Tools & Settings > Updates > Web hosting > PHP interpreter versions.

 

[onki]

Hi,

I can't rollback to PHP 8.2 as my website on the same domain runs Joomla 6 and here the minimum PHP version is 8.3.
So I have set PHP 8.3 at the moment and hope Kolab will update to PHP 8.3 compatibility soon.

 

[NataliaA]

Hello Onki,

Please note that the website is not required to use PHP 8.2; it can run on any PHP version you need. "Plesk Premium Email, powered by Kolab" doesn't depend on the website's PHP settings.
PHP 8.2 simply needs to be installed on the server so that "Plesk Premium Email, powered by Kolab" can use it.

 

[onki]

PHP 8.2.30 is installed. Where do I have to configure the PHP version to be used with Plesk mail?

 

[onki]

Since PHP 8.2 is no longer supported since December 2025, Plesk shoult migrate Kolab to PHP to newer PHP versions quickly.

 

[Sebahat.hadzhi]

There shouldn't be any manual change needed for Premium Email to use PHP 8.2.
PHP 8.1 reached EOL in December, 2025. PHP 8.2 will reach EOL on December 31, 2026.

 

[onki]

In Plesk I have PHP 8.2.30 (FPM) active.
But Webmail does still not work properly.
Mail preview is not working as well as calendar and contacts.
EAS only syncs mails, not contacts and calendar.
What PHP mode is required (CGI, fast CGI, dedicated FPM, FPM)?