Message: The application has failed to start because its side-by-side configuration is incorrect.

Reference Number: KB-01046
Last Modified: May 19, 2020

This article will help you troubleshoot a Windows problem that might be encountered when installing Chief Architect software. If you are not yet using our home design software, please download a free trial of our Professional or DIY versions.

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The information in this article applies to:

Chief Architect Premier or Chief Architect Interiors  

Home Designer Professional or Home Designer Architectural or Home Designer Suite


When I try to install or update my Chief Architect software on my Windows-based system, I receive one of these warning messages.

"The application has failed to start because its side-by-side configuration is incorrect. Please see the application event log for more detail."

"An error occurred during the installation of assembly Microsoft.VC90.ATL,version=...publicKeyToken=..."

The program can't start because MSCVR120.dll is missing from your computer. Try reinstalling the program to fix this problem."

Why would one of these messages display, and how can I fix it?


This issue is typically caused by a conflict between the program and one or more of the files in the C++ runtime libraries. These libraries are part of the Windows operating system and are used, and potentially updated, by installing or updating several Microsoft or other third party products.


If you are experiencing this error when updating a program you currently have installed, please first run a Repair in order to ensure all of the program's files are installed correctly.

If the Repair option does not resolve the issue, the most effective method to correct this error is to uninstall and reinstall any Microsoft Visual C++ installations currently available on your computer before proceeding with the installation.

To repair your current installation

Please access the following Microsoft resource to learn how to repair an app or program, such as your Chief Architect software:

To uninstall all current Microsoft Visual C++ installations

Please access the following Microsoft resource to learn how to uninstall an app or program, such as the C++ libraries:

To reinstall new Microsoft Visual C++ packages

  1. Click each of the following links in order. If prompted, choose to Run the download to install each Microsoft Visual C++ Redistributable Package.

    Note:  If you are running Windows XP, or a 32-bit version of Windows Vista/7/8, it's only necessary to download the packages noted as "Redistributable Package (x86)."

    For more information on how to determine if you are running 32 or 64-bit Windows, see article "Determining If Your Computer is 32-Bit or 64-Bit" in the Related Articles section below.

  2. Once every package has been downloaded and installed, restart Windows.

  3. Finally, launch the program, or run the update, again.

If the error message persists after following all of these instructions, then you may need to contact a Microsoft Certified Technician to ensure that your Microsoft Visual C++ Runtimes are installed and operating properly.