PSI International

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Lightweight Candidate plugin

The PSI Lightweight Candidate requires a plugin to be installed for in application questions. This plugin supports Internet Explorer, Firefox and Chrome and requires the .NET framework 3.5 to be installed to be able to run. If using Chrome, it is also necessary to install a Chrome extension. Depending on system settings, the plugin might need explicit user authorization to run. The browser might ask for user permission through security prompts. These must be accepted in order for the plugin to run.

Possible Problems

The system requirements check reports the following problems:

  1. No plugin detected - the plugin is either not installed or blocked from executing
  2. No extension detected - the extension is either not installed or disabled (Chrome only)

No plugin detected

This problem occurs when the plugin is either not installed or blocked. It is also possible that the installation has become corrupt (for example, by deleting files by mistake). In that case, reinstall the plugin. It is not necessary to uninstall it first from the Windows Control Panel, but you can do so if you wish.

Installing .NET framework 3.5 or greater

The plugin requires the .NET framework version 3.5 or above to be installed. You should install the .NET framework before installing the plugin. You need administrator privileges to be able to install .NET. The .NET framework installer can be downloaded from the Microsoft website, where you can also find instructions on how to install it:

Obtaining and installing the plugin

You must be able to download an executable (.exe) file and must also have administrator privileges to be able to perform the installation. The plugin installer can be obtained in several ways. It can be provided to you directly by PSI, or you can download it from the ET2 server itself. A download link is provided on the system requirements page when starting an in application test if the plugin is not installed already. Alternatively, you can login to the ET2 server and download the installer from https://<<your ET2 server address here>>/s/lw/EKSLWPlugin.msi .

If getting the installer from the system requirements page, click the Download link to the right to download the installer. To install, simply run the installer and follow the prompts. Click Finish to complete the installation.

Check that the plugin is enabled

Internet Explorer

  1. on the Tools menu (gear icon), select "Manage add-ons"
  2. on the Show combobox on the left, select "All add-ons"
  3. look for "PSI Lightweight Candidate" under PSI AB
  4. if the status column says "Disabled" for the plugin, select that row and then click the "Enable" button on the bottom right of the window


  1. on the menu, select Add-ons (puzzle piece icon)
  2. on the left, select Plugins
  3. look for "PSI Lightweight Candidate Plugin"
  4. check that the combobox directly to the right says "Ask to Activate" or "Always Activate". If not, change it to one of these two options (Always Activate is recommended).


No further checks necessary after installation.

No extension detected

This problem occurs only in Chrome, when the extension is not installed or is disabled. To install the extension, click the "Add to Chrome" button to the right on the system requirements page. You will see a popup dialog asking for your permission to install the extension. Click "Add extension" to install. If there is any problem installing the extension, you will get another popup describing the problem. If this happens, the "Add to Chrome" button will disappear and in its place will be a "Install Extension" link. Click it to be forwarded to the Chrome Web Store listing for the PSI Lightweight Candidate extension. Click "Add to Chrome" on the top right to install. Alternatively you can also browse to the Chrome Web Store listing for the extension and install it directly from there:

To check if the extension is enabled, follow these steps:

  1. open chrome://extensions/ on a new tab (or select Settings from the menu, followed by Extensions on the left)
  2. look for PSI Lightweight Candidate on the list and make sure the checkbox next to "Enable" is on (the icon will be greyed out if the extension is disabled)
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