With one exception, no. We do encourage running Virus Blocker and Virus Blocker Lite at the same time. This is due to the fact that Virus Blocker leverages the BitDefender virus signature set and Virus Blocker Lite utilizes the ClamAV set, providing an extra layer of scanning.
In most cases you should only run the paid version of each application, such as Web Filter or Spam Blocker. The Lite versions usually have less features and running both can double your administration workload, so we recommend against running both.
If you are using one version of an application (paid or lite) and you wish to install the other but it is not available from the 'install apps' menu, there are a few steps to take. First, you'll remove the version you are currently using. Once that's done, the other version will become available to install. If you wish install Web Filter but Web Filter Lite is already installed, first navigate to Web Filter Lite > Settings> and then click 'remove' at the bottom-left.