Plesk upgrade hangs on Ubuntu: Setting up plesk-dovecot-imap-driver

Symptoms

• Plesk upgrade hangs on the following step:

  PLESK_INFO: Setting up plesk-dovecot-imap-driver

• It is not possible to switch from Courier to Dovecot via Plesk Installer.

• The server has a kernel version older than 4.4.0-66-generic:

  # uname -r
  4.4.0-31-generic

• AppArmor is enabled on the server:

  # apparmor_status
  apparmor module is loaded.

Cause

This is an Ubuntu bug, which may occur when a server has an old kernel and AppArmor is enabled.

Resolution

Permanent solution is upgrading kernel to the version at least 4.4.0-66-generic.

As a workaround, temporary disable AppArmor and perform a Plesk upgrade/installation of Dovecot.

Alternative workaround:

1. Log in to Plesk server via SSH

2. Remove the package:

# dpkg -r --force-depends plesk-dovecot-imap-driver

# apt-get install -f

3. Install Plesk updates:

# plesk installer

4. Re-install the package:

# apt-get install --reinstall plesk-dovecot-imap-driver