Application Has Failed To Start- Side-By-Side Configuration Is Incorrect | Fast Fix Steps

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The side-by-side configuration is incorrect error often means broken Visual C++ runtimes, and reinstalling the needed packages lets the app open.

Seeing this message when you launch a program on Windows can be confusing. The text looks technical, the app will not open, and the dialog repeats every time you try. The same text can appear across many different applications on the same PC, and it always looks mysterious enough. The good news is that side-by-side configuration problems follow a small set of patterns, so you can work through them in a calm, methodical way.

What This Side-By-Side Error Actually Means

When Windows loads an application, it does not only read the main EXE file. It also reads a small manifest that lists which shared libraries and Visual C++ components the program expects. Side-by-side configuration is incorrect messages appear when that manifest points to a library version that is missing, damaged, or mismatched.

Many desktop programs depend on Microsoft Visual C++ Redistributable packages. These packages install common runtime files so that every app does not need to ship its own copy. If one of those packages is missing or corrupted, your program asks for a specific build, Windows cannot match it, and the application has failed to start side-by-side configuration is incorrect dialog shows up.

On modern Windows releases, side-by-side assemblies live under the WinSxS folder and carry long names with version numbers, processor type, and language. When a program asks for one of those assemblies, the loader checks that folder for an exact match. If the match fails, the loader does not guess or pick a close entry, and the side-by-side configuration is incorrect warning appears.

Common Triggers For This Message

  • Missing Visual C++ package — The app needs a redistributable that is not installed at all.
  • Wrong Visual C++ build — A similar package is present, but the exact build in the manifest is different.
  • Damaged runtime files — The correct redistributable exists, yet one or more DLL files are broken or deleted.
  • Corrupt application manifest — The XML manifest inside the app points to libraries that do not exist on disk.
  • System file problems — Core Windows side-by-side components are damaged by crashes or malware.

Quick Checks Before You Try Deep Fixes

Before you change packages or run long scans, it pays to clear simpler causes. Many side-by-side configuration errors come from a bad install attempt or a temporary glitch inside Windows.

  • Restart Windows — A clean restart clears locked files and stale side-by-side cache entries.
  • Try Another User Account — Log in with a different local account and launch the same app to see whether the error follows the profile.
  • Run As Administrator — Right-click the shortcut, choose Run as administrator, and see whether the program starts.
  • Check Other Apps — Open another program that depends on Visual C++, such as a different game or editor, to learn whether the issue is system wide.
  • Install Pending Updates — Open Windows Update, install all available patches, then restart and test the application again.

If every affected program is from the same vendor, the problem may sit inside that product family. If many unrelated tools show the same dialog, you are more likely looking at a broken Visual C++ runtime or damaged system files.

Fix Side-By-Side Configuration Is Incorrect Errors With Visual C++

In a large share of cases, the quickest real fix is to reinstall the Visual C++ redistributable packages that the app expects. This refreshes the shared runtime files that side-by-side uses to satisfy manifest requests.

Check The Exact Package In Event Viewer

Event Viewer can show which runtime build fails. Press Windows + R, type eventvwr.msc, and press Enter. Under Application logs, look for an error entry from SideBySide at the time you saw the pop up. The text often lists a version of Microsoft.VC90.CRT, Microsoft.VC80.CRT, or a later family, which hints at the matching Visual C++ release year.

Download And Reinstall Visual C++ Packages

Once you know the likely family, reinstall the redistributables from the official Microsoft download pages. Always pick both x86 and x64 builds on a 64-bit system, because many apps still ship as 32-bit.

  • Remove broken installs — Open Settings, then Apps, then Installed apps, and uninstall any Visual C++ package that shows errors or partial installs.
  • Download fresh copies — Visit the Microsoft download center, search for the matching Visual C++ redistributable names, and save the installers.
  • Install x86 then x64 — Run the 32-bit installer first, then the 64-bit installer, and accept the default options.
  • Restart and test — After installers finish, restart Windows and launch the affected application again.

The table below gives a rough link between common side-by-side error text and the family of Visual C++ package that often resolves the issue. Always match this with what you see in Event Viewer for your own system.

Error hint in log Visual C++ family Notes
Microsoft.VC80.CRT Visual C++ 2005 Install both SP1 x86 and x64 builds.
Microsoft.VC90.CRT Visual C++ 2008 The 2008 SP1 redistributable often clears this error.
Microsoft.VC100.CRT or later Visual C++ 2010 and newer On current Windows releases, 2015–2022 packages are common.

It is normal to see many different Visual C++ entries in Apps and Features. Each entry serves programs built with a specific toolset, so removing old ones just to tidy the list can trigger new side-by-side errors. Leave these packages in place unless you know a specific entry came from broken setup media or a test install that you no longer use.

Fix Application Manifests And Corrupted System Files

If reinstalling Visual C++ does not change anything, the app manifest or core Windows side-by-side engine may be damaged. You can gather more detail with the built-in sxstrace tool, then repair core files with System File Checker and DISM.

Capture A Trace With Sxstrace

  • Open Command Prompt — Press Windows key, type cmd, right-click Command Prompt, and pick Run as administrator.
  • Start the trace — Run sxstrace trace -logfile:sxstrace.etl and leave the window open.
  • Reproduce the error — Launch the problem application until you see the side-by-side configuration is incorrect dialog again.
  • Stop the trace — Go back to Command Prompt and run sxstrace stoptrace.
  • Convert the log — Run sxstrace parse -logfile:sxstrace.etl -outfile:sxstrace.txt and then open the text file in Notepad.

The parsed log shows which manifest file Windows tried to load and which DLLs it could not match. If the manifest lives next to the EXE and points to a folder that no longer exists, reinstalling the app or running its built-in repair tool is usually the cleanest path.

Repair Core Windows Files

  • Run System File Checker — In an admin Command Prompt, run sfc /scannow and wait until the scan reaches one hundred percent.
  • Repair component store — On Windows 10 or 11, follow with DISM /Online /Cleanup-Image /RestoreHealth to refresh the local image.
  • Restart the device — After both commands complete, restart Windows, then try the same program once more.

These tools scan and repair many shared libraries that side-by-side uses for manifests and C runtime binding. If they find and fix corruption, the application may start without any further changes.

Reinstall Or Repair The Problem Application

Some programs ship their own manifest and private copy of runtime files inside their folder. In those cases, a broken install or a partial update on that one product can trigger a side-by-side configuration is incorrect message even when the system runtimes look healthy. If the application has failed to start- side-by-side configuration is incorrect alert only appears for one tool, that points straight at its own files.

  • Back up settings — Save any custom profiles or data that live inside the program folder or under your user AppData path.
  • Uninstall cleanly — Use Settings or Control Panel to remove the application, then restart once it has been removed.
  • Remove leftover folders — After the restart, delete any remaining program folders under Program Files, Program Files (x86), and your user profile, while leaving shared folders alone.
  • Download the latest installer — Get a fresh copy of the installer from the vendor site rather than reusing an old setup file.
  • Install as administrator — Right-click the installer, choose Run as administrator, and follow the prompts.

If the vendor offers a Repair option in Apps and Features, you can try that before a full uninstall. Repair runs through the manifest and private runtime files that ship with the program and often restores missing or damaged components.

What To Do When Application Has Failed To Start- Side-By-Side Configuration Is Incorrect Still Appears

Sometimes the dialog remains even after you reinstall Visual C++ packages and the program itself. At this stage you know that the issue is persistent and tied either to a very specific manifest mismatch or to deeper Windows damage.

  • Check 32-bit versus 64-bit mix — If you run a 32-bit app on 64-bit Windows, it still needs the 32-bit Visual C++ package; make sure the x86 build is in place.
  • Compare with a second machine — If you have access to another PC where the same app works, compare installed Visual C++ packages and note any missing builds.
  • Scan for malware — Run a full scan with Windows Security and a trusted on-demand scanner, then remove any threats.
  • Create a new Windows account — Make a fresh local user, log in, install the app just for that account, and see whether it launches.
  • Use System Restore — If the error began right after a driver or software change, roll the system back to a restore point from an earlier day.

If none of these steps help and the application has failed to start side-by-side configuration is incorrect message still blocks your work, you may be looking at a deeper Windows install issue. At that stage, an in-place upgrade repair of Windows or a clean install, with backups in place, becomes the honest next step.

Prevent Side-By-Side Errors On Windows

Once your program launches again, it makes sense to lower the odds of seeing this dialog later. Side-by-side problems often show up after rushed installs, disk damage, or untested registry cleaners.

  • Install software from trusted sources — Stick to vendor sites or well known stores instead of random mirrors.
  • Avoid aggressive cleaners — Skip tools that delete DLLs or registry entries without clear explanations.
  • Keep Windows updated — Regular system updates refresh many shared components that apps rely on.
  • Back up before big changes — Create a restore point or backup image before major driver or app installs.
  • Watch for installer warnings — When a setup program reports a failed component, stop and resolve that error instead of clicking past it.

With these habits in place, application has failed to start- side-by-side configuration is incorrect messages should stay rare. When they do appear, you now have a clear path to trace the missing runtime, repair broken files, and bring your programs back to life.