A fatal error has occurred
Unable to open VFS file.
in /usr/share/php7/PEAR/Horde/Vfs/Ssh2.php:173
1. Horde_Registry->callAppMethod() /srv/www/vhosts/de-korte.org/horde/services/download/index.php:32
2. Gollem_Application->download() /usr/share/php7/PEAR/Horde/Registry.php:1197
3. Horde_Vfs_Ssh2->readStream() /srv/www/vhosts/de-korte.org/horde/gollem/lib/Application.php:328
Details
The full error message is logged in Horde's log file, and is shown below only to administrators. Non-administrative users will not see error details.
Horde_Vfs_Exception Object
(
    [details] =>
    [logged] => 1
    [_logLevel:protected] => 0
    [message:protected] => Unable to open VFS file.
    [string:Exception:private] =>
    [code:protected] => 0
    [file:protected] => /usr/share/php7/PEAR/Horde/Vfs/Ssh2.php
    [line:protected] => 173
    [trace:Exception:private] => Array
        (
            [0] => Array
                (
                    [file] => /srv/www/vhosts/de-korte.org/horde/gollem/lib/Application.php
                    [line] => 328
                    [function] => readStream
                    [class] => Horde_Vfs_Ssh2
                    [type] => ->
                )

            [1] => Array
                (
                    [file] => /usr/share/php7/PEAR/Horde/Registry.php
                    [line] => 1197
                    [function] => download
                    [class] => Gollem_Application
                    [type] => ->
                )

            [2] => Array
                (
                    [file] => /srv/www/vhosts/de-korte.org/horde/services/download/index.php
                    [line] => 32
                    [function] => callAppMethod
                    [class] => Horde_Registry
                    [type] => ->
                )

        )

    [previous:Exception:private] =>
)