Fixing “Side-by-Side Configuration” Errors During Excel Installation

When you attempt to launch Excel or run an installation setup file, Windows may block execution with an error dialog:

• “The application has failed to start because its side-by-side configuration is incorrect. Please see the application event log or use the command-line sxstrace.exe tool for more detail.”

This error indicates that Excel’s executable manifest file requested a specific version of the Microsoft Visual C++ Redistributable Runtime, but the operating system cannot locate a matching, uncorrupted version within the Windows Side-by-Side (WinSxS) native library directory.

Quick Answer

This issue is almost always resolved by repairing or reinstalling the Microsoft Visual C++ Redistributable packages:

1. Download both the x86 and x64 installers for the latest Visual C++ 2015–2022 Redistributable directly from Microsoft’s official support portal.
2. Run both installers, select Repair (or Install if missing), and restart your computer.

If installing the runtimes fails to resolve the error, run an administrative system scan: open Command Prompt as Administrator, run sfc /scannow, and restart your PC.

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What Causes a Side-by-Side (WinSxS) Failure?

Modern Windows applications rely on manifests embedded within .exe and .dll binaries. These manifests declare the exact assembly dependencies required to run the program—such as C/C++ standard runtime libraries, common controls, and GDI graphics modules.

The Windows WinSxS (C:\Windows\WinSxS) directory allows multiple versions of the same shared libraries to run concurrently (“side-by-side”) without file conflicts.

Excel.exe (Manifest Request)
 │
 ├── Checks WinSxS Assembly Store for Visual C++ Runtimes
 │    ├── Case A: Runtime Found & Verified ───────> Excel Boots Successfully
 │    ├── Case B: Runtime Missing or Corrupted ──> Side-by-Side Error
 │    └── Case C: Registry Link Damaged ──────────> Side-by-Side Error

A Side-by-Side error is triggered during Excel setup or launch when:

1. Missing Visual C++ Libraries: Excel requires specific builds of the Visual C++ runtime that are not present on the computer.
2. Corrupted Assembly Manifests: A system crash, forced shutdown, or bad disk sector damaged the XML manifest entries in the WinSxS cache.
3. Corrupted Registry Activation Contexts: Registry keys under HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\SideBySide point to files that have been deleted or modified.

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Step-by-Step Diagnostic and Repair Procedure

Work through these steps in order to isolate and repair the damaged assemblies.

Step 1: Pinpoint the Missing Assembly Using SxSTrace

Instead of guessing which runtime component is broken, use the Windows diagnostic tracing tool to identify the exact missing library.

1. Open the Start menu, type cmd, right-click Command Prompt, and select Run as Administrator.
2. Start the diagnostic trace by typing: sxstrace.exe Trace -logfile:sxstrace.etl
3. Press Enter. The console will say: Tracing started. Characterization stored in file sxstrace.etl.
4. Without closing the command prompt, attempt to launch Excel or run the installer to trigger the Side-by-Side error popup. Click OK on the error dialog to dismiss it.
5. Return to the Command Prompt window and press Enter to stop the trace.
6. Convert the raw trace log into a readable text document by running: sxstrace.exe Parse -logfile:sxstrace.etl -outfile:sxstrace.txt

sxstrace.exe Parse -logfile:sxstrace.etl -outfile:sxstrace.txt

1. Open the generated file: notepad sxstrace.txt

notepad sxstrace.txt

1. Scroll to the bottom of the log. Look for the lines marked ERROR: or Resolve Partial Assembly failed.
   • The text will identify the missing component, such as:
     Microsoft.VC90.CRT,version="9.0.30729.1" (which corresponds to Visual C++ 2008) or
     Microsoft.VC140.CRT,version="14.0..." (which corresponds to Visual C++ 2015–2022).

• The text will identify the missing component, such as:
  Microsoft.VC90.CRT,version="9.0.30729.1" (which corresponds to Visual C++ 2008) or
  Microsoft.VC140.CRT,version="14.0..." (which corresponds to Visual C++ 2015–2022).

Step 2: Install or Repair Visual C++ Redistributable Packages

Once you identify the required runtime family (or if you prefer a blanket repair), download and run the appropriate standalone packages from Microsoft.

1. Close all running programs.
2. Download both the x86 and x64 architectures for:
   • Microsoft Visual C++ 2015–2022 Redistributable (Combined package)
   • If your SxSTrace log identified older dependencies, download the standalone Visual C++ 2010 SP1 or Visual C++ 2008 SP1 packages.

• Microsoft Visual C++ 2015–2022 Redistributable (Combined package)
• If your SxSTrace log identified older dependencies, download the standalone Visual C++ 2010 SP1 or Visual C++ 2008 SP1 packages.

1. Important: On 64-bit operating systems, you must install both the x86 and x64 versions, because 64-bit Windows routes 32-bit application requests through the 32-bit runtime layer.
2. Run each installer. If the setup package offers a Repair button, click Repair. If only Install is available, complete the standard installation.
3. Restart your computer once all packages finish.

Step 3: Repair the Component Store (SFC & DISM)

If reinstalling the Visual C++ packages does not clear the error, the WinSxS component directory itself has corrupted XML manifests or damaged file links.

1. Open Command Prompt as Administrator.
2. Run the Windows Deployment Image Servicing and Management (DISM) tool to restore the system component store from local or cloud-backed sources: DISM.exe /Online /Cleanup-image /Restorehealth

DISM.exe /Online /Cleanup-image /Restorehealth

1. Allow the operation to reach 100%. (This may take 10–15 minutes depending on system resources).
2. Once completed, run the System File Checker to scan for and repair corrupted protected binaries: sfc /scannow

sfc /scannow

1. Look for the final message: “Windows Resource Protection found corrupt files and successfully repaired them.”
2. Restart the computer and run the Excel installer or launch Excel.

Step 4: Perform a Clean Reinstall of Office

If the error persists specifically when running the Office installation package (Click-to-Run), an earlier installation attempt left partially extracted executable stubs in hidden system directories.

1. Download the official Microsoft Office Uninstall Support Tool (SetupProd_OffScrub.exe) from Microsoft’s account portal.
2. Run the tool to completely remove all traces of current and legacy Office versions, temporary setup files, and registry entries.
3. Restart your computer.
4. Sign in to your Microsoft Account dashboard at account.microsoft.com and download a fresh, complete offline or online setup package.
5. Right-click the downloaded setup installer and choose Run as Administrator.

If your installation succeeds but encounters runtime execution failures when opening existing macro-enabled files, see Fixing “Side-by-side configuration” errors during Excel installation. for guidance on mapping custom third-party dynamic libraries.