How to Stop Microsoft AutoUpdate from Trying to Update Silverlight

If you are searching for exactly stopping Microsoft AutoUpdate from Trying to Update Silverlight, the solution requires removing specific ghost files from your macOS system library. Microsoft officially ended support for the Silverlight web framework in October 2021. Despite this, the Microsoft AutoUpdate (MAU) utility on Mac frequently gets confused by leftover installation files, triggering endless update prompts or persistent update failure notifications. Because modern browsers no longer load Silverlight, keeping it on your system serves no purpose. To resolve this loop permanently, you must manually delete the deprecated plugin and its associated receipt files so the updater stops detecting it.

Remove the Legacy Silverlight Plugin File

The primary reason Microsoft AutoUpdate continues to push this update is that the original Silverlight plugin file is still sitting in your Mac's root Internet Plug-Ins folder. When MAU scans your local directories for Microsoft products, it sees this `.plugin` file and mistakenly believes an active installation requires patching.

• Step 1: Click on the Finder icon in your Mac dock to make it the active application.
• Step 2: In the top Apple menu bar, click on Go and select Go to Folder... from the dropdown menu, or press Command + Shift + G on your keyboard.
• Step 3: In the search field, type the exact path: /Library/Internet Plug-Ins/ and press Return. Ensure you do not type the tilde (~) symbol, as you need the root library, not your user library.
• Step 4: Scroll through the folder contents and locate the file named Silverlight.plugin.
• Step 5: Right-click (or Control-click) on the file and select Move to Trash.
• Step 6: Your Mac will prompt you for authentication because this is a system-level folder. Enter your administrator password or use Touch ID to authorize the deletion.

To verify this step, empty your Trash immediately. This action alone often stops the cycle, but leaving application support files behind can still cause MAU to throw false positives during future scans.

Clear Silverlight Application Support and Receipts

Even with the main plugin deleted, Microsoft AutoUpdate relies on package receipts and application support directories to catalog installed software. If a Silverlight folder remains in the Application Support directory, the updater may still attempt to pull down the latest deprecated patch.

• Step 1: Open a new Finder window and press Command + Shift + G to open the path navigator again.
• Step 2: Type /Library/Application Support/Microsoft/ and hit Return.
• Step 3: Look for a folder named Silverlight. If it exists, right-click it and choose Move to Trash, providing your administrator password when prompted.
• Step 4: Open the path navigator one more time and navigate to /Library/Receipts/.
• Step 5: Search for any files beginning with com.microsoft.installmac.silverlight. Delete these `.bom` or `.plist` receipt files if you find them.

Once you have cleared these directories, restart your Mac. After rebooting, open Microsoft Word, click on Help in the top menu bar, and select Check for Updates. The Microsoft AutoUpdate window will populate, scan your drive, and return a list of actual pending updates for your Office suite, with Silverlight completely absent from the queue.

Reset the Microsoft AutoUpdate Configuration Cache

In rare instances, MAU caches its previous scan results. If you have deleted all Silverlight files but the update prompt still appears, you must force the AutoUpdate utility to forget its previous state by trashing its configuration file.

• Step 1: Quit Microsoft AutoUpdate if it is currently running.
• Step 2: Click the Finder icon, press Command + Shift + G, and type ~/Library/Preferences/ (this time including the tilde symbol for your specific user library).
• Step 3: Locate the file named com.microsoft.autoupdate2.plist and drag it to the Trash.
• Step 4: Relaunch any Microsoft application, such as Excel, and trigger the update check via the Help menu. MAU will generate a fresh configuration file and perform a clean scan of your local drive, finally recognizing that Silverlight is gone.

Streamline Your Document Workflow with WPS Office

Dealing with fragmented background updaters and legacy system remnants can severely disrupt your productivity. If you are frustrated by the heavy footprint of traditional office software and want an environment that avoids legacy bloatware, WPS Office provides a highly optimized alternative. Instead of installing separate heavy applications for Word, Excel, and PowerPoint—and relying on independent background utilities like Microsoft AutoUpdate to patch them—WPS Office consolidates your entire workflow into a single, lightweight application.

WPS Office offers native compatibility with `.docx`, `.xlsx`, and `.pptx` formats, ensuring you can seamlessly collaborate with colleagues using other suites. Because it operates natively without requiring outdated web frameworks or intrusive background scanners, you will never face phantom update prompts. Furthermore, WPS Office integrates advanced PDF editing tools directly into its core interface. You can split, merge, annotate, and convert PDFs to editable text documents within the same tabbed window where you manage your spreadsheets and presentations, eliminating the need to purchase or update third-party PDF readers.

Frequently Asked Questions

Why does Microsoft AutoUpdate detect an uninstalled program?

Microsoft AutoUpdate does not scan your active applications to see what you are currently using; instead, it looks for specific package receipts and `.plugin` files placed on your hard drive during the original installation. If you previously uninstalled Silverlight simply by dragging an app icon to the trash instead of removing the root system library files, MAU still reads the leftover installation receipts and believes the software requires an update.

Is it safe for my Mac if I delete the Silverlight plugin?

Yes, it is entirely safe and highly recommended. Silverlight is obsolete software that reached its end-of-life status in late 2021. No modern web browser—including Safari, Chrome, Edge, or Firefox—supports the Silverlight framework anymore. Deleting it frees up a small amount of disk space, closes potential legacy security vulnerabilities, and stops the persistent updater errors without affecting any modern applications.

Will removing Silverlight break my Microsoft Word or Excel software?

No, your core productivity applications will function correctly. Silverlight was a web application framework designed for streaming media and running rich internet applications in a web browser, functioning similarly to Adobe Flash. It is completely independent of the desktop Office suite. Deleting it will have absolutely no negative impact on Word, Excel, PowerPoint, or Outlook.

How do I prevent Microsoft AutoUpdate from installing automatically in the future?

While you cannot easily uninstall MAU without breaking the update mechanism for your core Office apps, you can stop it from running automatically in the background. Open Microsoft AutoUpdate, click on the "Automatically keep Microsoft Apps up to date" checkbox to deselect it, or click the "Advanced" button and change the update channel settings to manual. This gives you full control over when the system scans your drive and downloads patches.