Office Apps Not Opening

How to Fix Procedure Entry Point Error in Office or Windows Calendar

Steve K Sep 28, 2026 870 views

Question details

The user encounters a procedure entry point error referencing olk.exe when attempting to open a calendar application.

How to Fix Procedure Entry Point Error in Office or Windows Calendar

Product: Microsoft Office / Windows Calendar
Device & OS: Windows
Scenario: Launching the Windows Calendar or Outlook calendar application.
Observed behavior: An error message appears referencing olk.exe in the WindowsApps folder, which prevents the calendar application from opening successfully.

Before you start

Before proceeding, determine whether the error appears when opening the classic Outlook Calendar or the default Windows Calendar application, and take a screenshot of the complete error message for reference.

Solution 1Recommended

Install Pending Windows and Office Updates

Updating your operating system and Office applications can resolve compatibility issues and bugs introduced by previous updates.

Procedure entry point errors are often caused by version mismatches between system files and application components. Keeping Windows and Office up to date ensures all dependencies are properly aligned.

Check for Windows Updates

Open Windows Settings, navigate to 'Update & Security' (or Windows Update), and click 'Check for updates'. Install any pending updates and restart your computer.

Update Microsoft Office

Open any accessible Office application like Word or Excel. Go to File > Account, click on 'Update Options', and select 'Update Now'.

Update through Microsoft Store

If you are using the default Windows Calendar app, open the Microsoft Store, go to 'Library' in the bottom left corner, and click 'Get updates' to update the Mail and Calendar apps.

Install Pending Windows and Office Updates

Important: If the error began immediately after a recent update, note your application version and report it to Microsoft Support, as it may be a known bug requiring a hotfix.

Solution 2

Repair the Affected Calendar Application

Using the built-in Windows repair tool can fix corrupted files or missing components in Office or Windows Calendar without deleting your data.

Solution 3

Switch to the New Outlook App

Microsoft is transitioning away from the legacy Windows Calendar app. Switching to the newer version can bypass legacy architectural errors.

Free Microsoft Office alternative

Experience a Bug-Free Office Suite with WPS Office

If Microsoft Outlook or Windows Calendar continues to display complex entry point errors, consider switching to WPS Office. It provides a lightweight, highly compatible alternative for managing your documents, spreadsheets, and presentations without the bloatware.

1. Download the Installer: Visit the official WPS Office website and click the free download button.
2. Install WPS Office: Run the downloaded executable file and follow the quick installation instructions.
3. Open Your Files: Launch WPS Office to immediately view, edit, and create documents with full compatibility.

Completely free and lightweight Office alternativeSeamless compatibility with Microsoft Office formats (DOCX, XLSX, PPTX)Familiar tabbed interface for quick and easy migrationStable performance without complex WindowsApps folder errors

microsoft office alternative - wps office

Frequently Asked Questions

What is olk.exe in the WindowsApps folder?

Olk.exe is the executable file for the 'New Outlook for Windows' application, which Microsoft uses to replace the older Mail and Calendar applications. The error occurs when this file is corrupted, missing, or conflicting with older app settings.

Why do I get a procedure entry point error after a Windows update?

Application updates or OS patches can sometimes introduce temporary compatibility issues or fail to register dynamic-link library (DLL) files correctly. When a program tries to call a function that wasn't updated properly, the system throws an entry point error.

How do I report a persistent Calendar app bug to Microsoft?

You can report unresolvable bugs using the Windows Feedback Hub. Press the Windows Key + F to open the Hub, describe the procedure entry point error in detail, attach a screenshot of the error dialog, and submit it for Microsoft Support to review.

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