When I try to install Tekla Tedds and/or Tekla Structural Designer, the installation fails with an error message such as "Error 1638" or "Error 1603." What should I do?

Problem

You run the installation for Tekla Tedds and/or Tekla Structural Designer, but the installation fails and may give one of the error messages below:

• Error: 1638 — Another version of this product is already installed. Installation of this version cannot continue. To configure or remove the existing version of this product, use Add/Remove Programs on the Control Panel. This setup will now exit!
• Error: 1603 — Fatal error during installation. This setup will now exit!

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Resolution

In general, these are generic Microsoft Windows Installer (MSI) errors, often caused by system-related issues like missing permissions, corrupted files and/or installation records, or antivirus software conflicts.

In the case of Error 1638, the installer may be unnecessarily trying to install a Microsoft Windows component that is already installed.

In these cases, you can complete the installation by manually installing the necessary components for Tekla Tedds and/or Tekla Structural Designer via the Install Cache. Please follow the steps below to do this:

1. Ensure all instances of Tedds, Tedds for Word, and/or Tekla Structural Designer are closed.
2. Browse to the following folder in Windows Explorer: C:\Program Files (x86)\Common Files\Tekla\Structural\Install Cache.
3. There may be multiple cached install folders inside this folder - one for each software version that has been installed. The cached install folder(s) will be named "setup_tekla_structural_design_[year]_[month][year]," where month and year are the version and release year and month. For example, for the 2025 release, the folder will be called "setup_tekla_structural_design_2025_march2025."

4. Locate and open the folder for the version you are trying to install, then the "Modules" folder inside this.
    

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5. The Modules folder will contain multiple subfolders - one for each installation component. Work through these subfolders one by one:

   1. Open a subfolder.
   2. Locate the .msi (Windows Installer Package) file within it.
   3. Double-click the .msi file to run the installer.
   4. Follow the prompts, and select the "Repair" option if prompted.
   5. Allow the installer to complete and close before moving on to the next subfolder.
       
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6. Repeat step 5 until all the components are installed (LicenseService, LicenseService64, StructuralDesigner, Tedds, Tedds64, TeddsEngineering).

If you wish to spend time troubleshooting the problem or are unable to follow the steps above successfully, please contact your local support team for further assistance. You can submit a support request using the contact form here.