Fix the Office Side-by-Side Configuration Error in Excel and Outlook
Question details
The user needs to resolve a side-by-side configuration error that prevents Excel and Outlook from opening.
- Product
- Microsoft Office, including Excel and Outlook
- Device & OS
- Windows (version not provided)
- Scenario
- Opening Excel or Outlook on a Windows computer
- Observed behavior
- Both applications fail to start and report that their side-by-side configuration is incorrect.
Note the exact error message and when it appears. Check your Windows version under Settings > System > About, and locate your Office version in the installed apps list if the applications will not open.
Check the Windows event log for the failing component
Use the SideBySide event details to identify the dependency or configuration involved before choosing a repair.
Open Excel or Outlook from the Start menu and note the time when the side-by-side error appears.
Right-click the Start button, select Event Viewer, and expand Windows Logs > Application.
Look for an error with SideBySide as its source near the time of the failed launch. Open the event and review the General and Details tabs for the affected application and dependency.
If the event identifies a Microsoft Visual C++ runtime, obtain the matching supported redistributable from Microsoft's official download page and install or repair it. Then try opening the affected Office application again.
Repair the Microsoft Office installation
Try Office Repair if the Office installation is damaged or the event log does not point to a separate dependency.
Open Excel Workbooks with WPS Office
WPS Office is a free, lightweight, easy-to-use alternative for working with Office documents. Its familiar interface and support for common Microsoft Office formats make it easy to move your files. It does not repair the Windows or Office error, and it is not an Outlook email replacement.
Frequently Asked Questions
What does a side-by-side configuration error mean?
Windows could not load an application because of a configuration or dependency problem. Check Event Viewer > Windows Logs > Application for a SideBySide error to find more specific details.
Should I reinstall every Visual C++ redistributable?
Not necessarily. First check the matching SideBySide event in Event Viewer. If it identifies a Visual C++ runtime, use Microsoft's official download page to obtain the appropriate supported package.
How do I repair Office if Excel will not open?
In Windows Settings, go to Apps > Installed apps, select Microsoft 365 or Microsoft Office, and choose Modify. Run Quick Repair or, if needed and available, Online Repair.
What information should I collect if the error continues?
Record your Windows version from Settings > System > About, your Office version from the installed apps list, and the matching SideBySide event details from Event Viewer > Windows Logs > Application.
