Frequently Asked Questions (FAQs)

About LewaPlus®

  • How much does LewaPlus cost?
    LewaPlus can be downloaded and used free of charge. However, you have to register for a license.
  • Are upgrades free?
    Yes. From time to time LANXESS makes available bug fixes and enhancements for LewaPlus. These can be installed using the LewaPlus update facility which is part of the LewaPlus application.
  • Does LewaPlus support other languages than English?
    Yes, LewaPlus has built in support for internationalization. In principle the user interface of LewaPlus can support most languages of the world provided that the required language resource files are available. Starting with version 1.6 the following 10 languages are supported: English, German, French, Spanish, Russian, Turkish, Chinese, Italian, Portuguese (Brazil), and Japanese. Additional languages will follow.
  • Not all languages officially supported by LewaPlus are selectable in the preferences of LewaPlus. Why?
    Only those languages are selectable, which are supported by the Windows operating system, too. Windows support is not installed for all languages by default. Only, after Windows support has been installed for the requested language, it is also selectable in the preferences of LewaPlus.


  • I didn't receive the email with the LewaPlus license and installation instructions. What should I do?
    In rare cases it might occur that you do not receive the email with the LewaPlus license and installation instructions. In that case please check the spam folder of your email account or send an email to lewaplus@lanxess-info.com
  • I can't open the license file I received by e-mail. What should I do?
    Although the LewaPlus license file is a simple Unicode UTF-8 encoded text file, Windows might refuse to open it since the file type is not associated with an application. For a proper installation of the software it's not necessary for you to open the file. Just save the file to your hard disk and locate the file when the setup application asks for it.
  • I get a file open security warning when I start the setup application. What should I do?
    Windows issues such a warning for applications you downloaded from the Internet or copied from another computer. Starting with LewaPlus version 1.1 the setup application is digitally signed, that is, Windows will display the name of "LANXESS Deutschland GmbH" as the publisher of the software and you can inspect the certificate. If you downloaded the LewaPlus setup application from this website and see "LANXESS Deutschland GmbH" named as the publisher you can safely continue to run the setup application.
  • On installation I get the error message 'License file format invalid' or 'License invalid'. What should I do?
    These errors occur when the content of the LewaPlus license file was corrupted or altered accidentally. Please make sure you have an unaltered copy of the license file you received by e-mail saved on disk. If the problem persists, please contact the LewaPlus Support team.
  • On installation I get the error message 'License expired'. What should I do?
    A LewaPlus trial license is valid for installing LewaPlus for 4 weeks after the license was issued only. Thereafter you get this error message. Please contact the Support team, if you want to extend the test period. A new trial license will be issued for you.

Licensing and support

  • What types of licenses are available for LewaPlus?
    LANXESS offers two types of licenses for LewaPlus: a 60 day trial license, and a permanent license. You start by registering for a trial license. After 30 days you will be asked whether you would like to apply for a permanent license, but you may apply at any time by invoking the 'register license' dialog from the help menu. If LewaPlus is a useful tool for you and you decide to apply for a permanent license, you will be asked to provide some additional information about yourself like additional contact information, your position in your company, and areas of interest. A request for approval is then sent to the LewaPlus support team. After approval a permanent license is sent to you by e mail.
  • How can I get a permanent license for continued use of LewaPlus™?
    You can apply for a permanent license (free of cost) at any time from within LewaPlus™ by selecting “Help / Apply for permanent license” from the main menu, filling out the displayed form, and submitting it. Permanent licenses are usually approved within 3 work days.
  • Can I use the same LewaPlus registration both at home and at work?
    Absolutely. You can use the same registered copy of LewaPlus on multiple machines as long as it is not used by another person.
  • How can I get support?
    Please contact the Support team, if the LewaPlus help and the FAQs don't answer your question.
  • Are you responsive to suggestions?
    Yes! The LewaPlus support team is delighted to receive feedback from our users. We want to build the best-of-breed design tool for Ion Exchange and Reverse Osmosis membrane systems so getting back 'reports from the field' will help us to serve you better.

Technical issues

  • What platforms are supported by LewaPlus?
    All recent 32-bit desktop Microsoft Windows platforms are supported – that's Windows XP SP3, Windows Vista, Windows 7, Windows 8 and Windows 10. LewaPlus is also compatible with the 64-bit versions of Windows 7 / 8 / 10.
  • I get errors when applying for a permanent license or when checking for LewaPlus updates. Why?
    LewaPlus has to access the Internet to perform these actions. If this doesn’t work it’s very likely that your computer is located behind a company firewall and the LewaPlus network settings were not set correctly. Please choose the option “Extra/Preferences” from the LewaPlus main menu, select the tab “Network settings”, and adjust the proxy settings (for details see section “LewaPlus user interface/Preferences“ in the LewaPlus help). Starting with LewaPlus v1.1 the network settings dialog has a button to detect the proxy settings of your system. (For LewaPlus 1.0 it is necessary to enter user ID and password if the use of a proxy server is enabled, otherwise the application crashes when trying to access the Internet; this bug was fixed in version 1.1 and therefore these fields can be left empty for version 1.1 or later if the proxy server does not require authentication.)
    If the problem persists, please contact the Support team.
  • When I try to register my permanent license it is rejected as invalid. Why?
    This problem was mainly observed on computers using Windows configured for an East-Asian language. The LewaPlus license data are displayed in a text box and if this text box is not wide enough to display the data without line wrapping due to the system font size, the license data are corrupted by the automatically added line break. This bug has been fixed in LewaPlus v1.2.
    If you still use a prior version and are not able to update, please contact the LewaPlus Support Team for detailed instructions how to reinstall LewaPlus without loosing your LewaPlus project database.
  • When I try to update LewaPlus or to apply for a permanent license, I get an "invalid license" message. Why?
    Mid of March 2013 the architecture of the LANXESS web servers was changed. For LewaPlus versions lower than v1.3.2 this unfortunately causes the functions for updating or applying for a permanent license to fail with an "invalid license" message. Reinstalling LewaPlus using the latest setup is required. For users with permanent licenses the setup will detect an existing installation and will simply update it. Users with expired trial licenses who want to extend the test period or want to apply for a permanent license, please contact the Support team.
  • The LewaPlus update doesn't run properly. What should I do?
    Depending on your individual firewall and anti-virus software set-up, it might happen that the new update is blocked while downloading the update packages. We recommend to install the setup file. The setup will detect an existing LewaPlus installation and will offer to update it. The setup can be found on the LANXESS website:
    Please do NOT uninstall your LewaPlus software and reinstall it. In this case all your personal designs and projects would be lost (unless you make a backup of your project database first).
    For any further issues please contact lewaplus@lanxess-info.com
  • LewaPlus hangs on closing the application. What should I do?
    In version 1.10 a new tab was added to the LewaPlus main screen. Unfortunately the new screen layout could become corrupted if LewaPlus was closed using the close button (rex X button) in the upper right corner. Please do the following:
    1) Start LewaPlus
    2) Select menu entry "Extra / Restore layout"
    3) Close LewaPlus using the "Exit" button on the toolbar or menu entry "Project / Exit" (LewaPlus might hang one last time)
    4) Restart LewaPlus
    5) Close LewaPlus once again as described in step 3
    Thereafter the problem should not occur anymore.
  • The toolbar button "Check for updates" is grey. I can't update. What should I do?
    If LewaPlus was fixed to the Windows taskbar, on starting LewaPlus the toolbar button "Check for updates" is grayed out. The reason is that unfortunately the taskbar icon links to the wrong LewaPlus component. Please use the LewaPlus desktop icon to start LewaPlus. Then the "Check for update" button will be accessible.
  • The integrated LewaPlus update fails for version 1.12 or below. What should I do?
    For technical reasons the format of the LewaPlus update packages had to be changed in LewaPlus version 1.12. While for most users the transition was smooth, we received reports from some users for whom the update to the latest LewaPlus version failed. In case, you are affected by this upgrade problem, we recommend that you upgrade your LewaPlus installation using the latest LewaPlus setup available from the LANXESS LPT website (http://lpt.lanxess.com/en/lewaplus-software/) (big download button). Please download and execute the setup - it will usually detect your existing installation and will just update it. Keep in mind that Windows administrative rights are required. Please contact the LewaPlus support team, if you still experience problems in getting your LewaPlus installation to work properly. 
  • The user interface of LewaPlus appears blurry or pixelated, What should I do?
    This problem can occur in conjunction with Windows 7 or 10 and an High DPI display. It can be solved in the following way:
    1) Close LewaPlus
    2) Right-click on the LewaPlus desktop shortcut
    3) Open 'Properties' menu
    4) Change to tab 'Compatibilty'
    5) Activate the option 'Disable Display Scaling On High DPI'.
    6) Open LewaPlus again.