Fix Silverlight Issues

Click on the topic in the list below to go directly to the appropriate instructions:

General Steps to Fix Silverlight 

Silverlight is a browser plug-in (also called an add-on or add-in). If Silverlight does not load or run properly in your browser (displaying either a System Exception error, an error 4001, a blank page, or a blank frame without the menu items in Navigator Web), progressively implement each of the following steps until the problem is resolved

  1. Verify that Silverlight is installed (see below). Note: To install Silverlight in Internet Explorer on Windows 8 and 8.1, IE must be open in Desktop Mode.
  2. Ensure that the Silverlight plug-in is enabled - especially if you are using Firefox on a Mac OS X  
  3. Clear temporary Internet browsing files (see instructions to clear browsing History, Data, or Cache for your browser at "Fix Internet Browser Issues")
  4. Close all browser screens. Then re-start the browser and open the website for CTI Navigator Web first
  5. In Internet Explorer* 11, 10, or 9: 
    • select Tools in the browser menu and un-check "ActiveX Filtering" (for more information see "About ActiveX Filtering" by Microsoft) -   or 
    • click the Tools icon , select Safety, and un-check "ActiveX Filtering".
  6. For all Windows browsers, select Internet Options in the Windows Control Panel. (If Control Panel is set to "Category View", first select “Network and Internet” then select Internet Options.)  In Internet Explorer you can select Internet Options under Tools or Tools icon.  Then, on the Internet Options screen in the Control Panel or IE:
    • select Connections tab > LAN Settings button > Un-check "Automatically Detect Settings"; and  
    • select Advanced tab > under Accelerated Graphics, either check "Use software rendering instead of GPU rendering" if it is not checked (or un-check it if it is already checked and update the driver for your graphics card), OR  click here to run Microsoft's Fix-It utlity > restart the computer for changes to take effect.
  7. If Silverlight crashes frequently or fails to properly display all Navigator Web pages in Chrome or Firefox, install the IE Tab extension appropriate for your browser, and enable the IE Tab extension when running CTI Navigator Web.

  8. Close the browser with the problem, and open Navigator Web in a different browser.

If Silverlight is installed, enabled, and the browser's temporary Internet browsing files have been completely cleared, but Silverlight does not work properly in any browser on this computer, Un-install Silverlight and then install the latest version. If uninstalling and reinstalling Silverlight does not resolve the problem, see the "Clean Corrupted Silverlight Installation in Windows " or "Fix Silverlight in Mac" section below as appropriate. 

If Silverlight runs correctly in one browser but not correctly in another browser on your computer, the non-supporting browser itself may need to be reset, restored, un-installed and re-installed, or replaced by an earlier version. For instructions on managing browsers, see "Fix Internet Browser Issues" in the Related Articles at the end of this web page. 

Verify Silverlight Version Installed

To verify the version of Silverlight installed on a computer, click here (or go to  At this website Microsoft also provides install and uninstall instructions, and a chart of compatible operating systems and browsers for the version of Silverlight installed on your computer. If your installed version is earlier than the "current" (latest) version, you can click on the "Current version" number to install it on your computer if desired. 

To verify the version of Silverlight installed on a Mac, you can click Help and select "Installed Plug-ins" in the Safari browser menu. Then scroll down to view the Silverlight Plug-in information.

Note 1 - Compatibility: As of June 2012, only version 5 of Silverlight will run in a 64-bit version of Internet Explorer; and only version 4 of Silverlight will run correctly in Google Chrome on a Mac. While Silverlight version 5 can run in Chrome on a Mac, it does not support keyboard input (typing text). Silverlight is compatible with both Safari and Firefox on Macs. 

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Install Silverlight

Download Microsoft's latest Silverlight browser plug-in at "Download Microsoft Silverlight" (or select the desired version under Download Selected Version of Silverlight in the Related Articles at the end of this web page) using the method appropriate for your Internet browser and computer operating system. The basic installation steps are:  

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Enable Silverlight 

Normally add-ons/plug-ins such as Silverlight are automatically enabled when installed. However, they can be disabled manually or by other programs. 

To ensure that Silverlight is installed and enabled to run in Internet Explorer (8 and later):

  1. Open Internet Explorer
  2. Select Tools in the menu bar (or the gear icon in the top of the browser) 
  3. Select "Manage Add-ons"
  4. Under "Add-on Types", select "Toolbars and Extensions"
  5. Under "Show", select "All add-ons"
  6. Browse down to the Microsoft Corporation section, and select "Microsoft Silverlight"
  7. Verify or click the Enable button
  8. Click the Close button. 

To ensure that Silverlight is installed and enabled to run in Firefox 

  1. Open Firefox 
  2. Click Tools 
  3. Select Add-ons 
  4. Select Plugins 
  5. Beside "Silverlight Plug-in" verify or click the Enable button (or "Always Activate" on a Mac). 

To ensure that Silverlight is enabled to run in Chrome:

  1. Type "chrome://flags/#enable-npapi" in the browser URL/Search omnibox, scroll to "Enable NPAPI", and click the Enable button {Chrome version 42, 43, and 44 only.}
  2. Type "chrome://plugins" in the browser URL/Search omnibox, scroll to Silverlight,  and verify or click "Enable"; also check "Always allowed to run".

Note: If Silverlight is unstable (crashes) or you cannot enable Silverlight in Chrome in Windows, add the IE Tab extension to your Chrome. 

If you cannot type in a text or data entry box in Chrome on a Mac, uninstall version 5 and install version 4 (if available) of Silverlight.

To ensure that Silverlight is installed and enabled to run in Safari (6.0 and earlier):

  1. Open Safari 
  2. Click Help and select "Installed Plugins" in the top menu of the browser
  3. Scroll down to see "Silverlight plug-in"
  4. Close Help
  5. Open Preferences
    • In Mac: click Safari in the top menu and then select Preferences
    • In Windows: click Edit or Settings, and then select Preferences
  6. Select Security
  7. Beside Internet plug-ins, check "Allow all other Plug-ins" or see Safari 7 Plug-in Manager below
  8. Click Close. 

Safari Plug-in Manager in Mac (OS X)

To provide an extra level of security, starting with version 6.1 Safari automatically sandboxes (see sandbox note below) all plug-ins (such as Adobe Flash and Microsoft Silverlight) to limit their access to key system resources. However, Safari includes a plug-in manager that allows users to set the level of security to be enforced for specific plug-ins, either on a per website basis (such as just for the website where CTI Navigator Web runs for your MLS) or globally (for all other websites).

To set Safari (6.1 and later) to allow the Silverlight plug-in to run in unrestricted mode specifically on CTI’s website for your MLS (which is needed to support CTI Navigator Web functions performed in the browser on your computer):

  1. Open Safari to the CTI Navigator Web sign in page for your MLS
  2. Install Silverlight if it is not already installed 
  3. Click on the word "Safari" in the top left menu (next to the Apple icon) and select Preferences  (click to see image)
  4. Select the Security tab
  5. Beside Internet plug-ins (click for image):
    • Check "Allow Plug-ins"
    • Click on the "Manage Website Settings" button
  6. Click on Silverlight in the list of available plug-ins on the left  
          (click on image to enlarge)
  7. On the right, select the CTI Navigator website for your MLS (with an address formatted such as {YourMLS}
  8.  To give Silverlight unrestricted access to computer resources when running at the CTI Navigator website for your MLS, click "Run in Unsafe Mode"
      (click on image to enlarge)
  9. Beside “When visiting Other sites” (click to see image), select "Ask". 
    • Do not select "Allow" or “Allow Always” unless you intend for all websites to be allowed to use the selected plug-in (which is not necessary for CTI Navigator)
    • Do not select “Run in Unsafe Mode” for other websites because you might inadvertently visit some other (non-CTI) website that injects malicious code or malware through plug-ins.
  10. Click Done.
    • Click the Trust button when you are prompted to trust the CTI Navigator website for your MLS to run Silverlight in unsafe mode. This will change the website setting button to display "Allow Always " with a warning symbol (a triangle around an exclamation mark). This triangle symbol must be included in the setting!
    • You may need to close all open Safari screens for changes to take effect.

System Exception Error: if Silverlight cannot access needed computing resources (such as extra working memory), CTI Navigator Web functions may fail and display a "System Exception error" message. System Exception errors may not be fatal. Other Navigator Web functions may continue to operate correctly, and the failed function may recover if needed resources become unblocked or become available (such as by closing other browser screens or programs to free up working memory).

Sandbox Note. Sandboxing is a security mechanism to tightly restrict access to computer memory, operating system resources, and user files for unknown or untrusted code or unknown or untrusted websites.

Permissions Options:

Note that third-party plug-in managers (such as ClickToPlugin) may interfere with or override settings in Safari’s plug-in manager.

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Stabilize Silverlight in Chrome or Firefox in Windows using the IE Tab browser extension 

Click here for instructions on how to add the IE Tab extension to your Chrome browser in Windows.

Keep Silverlight Up-to-date

Enable the auto-update feature in Silverlight to ensure that your computer is using the latest Silverlight functionality and security.

  1. Right-click on a web page using Silverlight
  2. Left click on the word Silverlight
  3. Click the Updates tab on the Microsoft Silverlight Configuration screen
  4. Check "Install updates automatically (recommended)".
    • If this option is not available (when User Account Control is enabled in Windows), select "Check for updates, but let me choose whether to download and install them."
    • If neither option is available, update your Windows (because some component is out-of-date).

Uninstall Silverlight 

To uninstall Silverlight in Windows or Mac, follow the instructions below which are appropriate for your computer.

To uninstall Silverlight in Windows 7 or 8:

To uninstall Silverlight in Windows Vista:

To uninstall Silverlight in Windows XP or 2003:

To manually uninstall Silverlight on an Apple Mac:
  • Close all browser screens
  • Navigate to the hard drive where Silverlight is installed  
    • Yosemite OS (10.10): open Finder > click Go > select Computer > [optional: set view to List >] select Macintosh HD
    • pre-Yosemite OS (10.9 and earlier): open Finder > open Devices > select Macintosh HD
  • Navigate to your Library/ Internet Plug-Ins directory and drag any of the following to Trash: 
    • Silverlight.plugin (this is normally the only plug-in displayed for Silverlight)
    • WPFe.plugin (if displayed)
  • Also open /Library/Receipts and drag any of the following pkgs (if displayed) to the Trash:
    • Silverlight.pkg
    • Silverlight_W2_MIX.pkg
    • WPFe.pkg
  • Empty Trash. In the Finder drop-down menu, select "Empty Trash" or "Secure Empty Trash."  Silverlight will not be completely uninstalled until you empty the Trash. (You may need to restart your computer to ensure that all file components are removed.)

After completely un-installing all Silverlight components, re-install Silverlight (see "Install Silverlight in Mac" above). Then try to log into CTI Navigator Web again. 

For an alternative approach to finding and removing Silverlight components, see the video "How to Uninstall Silverlight on a Mac" at .

If you encounter difficulty completely removing all Silverlight components, either try using the Terminal command described below, or you might try using a Mac app removal utility such as the free AppCleaner from FreeMacSoft or a commercial product such as "CleanMyMac 2". Always use extra caution with all freeware. Otherwise, contact a Mac specialist either at Apple (phone 800-275-2273) or on the national Tech Helpline for your state Association of Realtors (FAR members can call 407-587-1450; and, until January 1, 2015,  GAR members can call 877-573-5611).

To automatically uninstall Silverlight from an Apple Mac

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Clean a Corrupted Silverlight Installation in Windows

If Silverlight does not work correctly in any browser on your Windows computer, and un-installing and then reinstalling Silverlight (see above) do not correct the problem, then its installation in Windows probably is corrupted. You can click here to download and run Microsoft's "Fix-it" automated troubleshooting and repair tool for Silverlight (for older versions of Windows click here to run Microsoft's "Fix it for me" wizard); or you can go to Microsoft's "How to clean a corrupted Silverlight installation and then reinstall Silverlight" website; or you can try to fix it yourself following Microsoft's instructions reprinted below from this website (see note 3 disclaimer below). 

Note 2: If Silverlight works in one browser but not another browser on the same computer, click here.  

If you are an advanced Windows user and want to try to resolve a corrupted Silverlight installation yourself:
  1. Click Start and type Notepad in the Search box
  2. Double-click on Notepad from the list of results above
  3. Copy and then paste the following text into Notepad:

    reg delete HKLM\Software\Microsoft\Silverlight /f
    reg delete HKEY_CLASSES_ROOT\Installer\Products\{D7314F9862C648A4DB8BE2A5B47BE100} /f
    reg delete HKEY_LOCAL_MACHINE\SOFTWARE\Classes\Installer\Products\{D7314F9862C648A4DB8BE2A5B47BE100} /f
    reg delete HKEY_CLASSES_ROOT\TypeLib\{283C8576-0726-4DBC-9609-3F855162009A} /f
    reg delete HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\App Paths\install.exe /f
    reg delete HKEY_CLASSES_ROOT\AgControl.AgControl /f
    reg delete HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\{89F4137D-6C26-4A84-BDB8-2E5A4BB71E00} /f
    rmdir /s /q "%ProgramFiles%\Microsoft Silverlight"
    rmdir /s /q "%ProgramFiles(x86)%\Microsoft Silverlight"

  4. Click File and Save As and type CleanSilverlight.cmd
  5. In the Save as type box, click All Files (*.*)
  6. In the Save in box, click Desktop, and then click Save
  7. On the File menu, click Exit
  8. Right-click the CleanSilverlight.cmd file on your desktop and click Run as administrator (in Windows XP click Run)
  9. When the uninstall completes, right-click the CleanSilverlight.cmd file on your desktop and click Run as administrator (in Windows XP click Run) a second time
  10. Once the uninstall has completed, click the link below to install the latest version of Microsoft Silverlight 

  11. Delete the CleanSilverlight.cmd file from your desktop.

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Fix Silverlight in Safari, Firefox or Chrome on a Mac

According to Microsoft, the minimum requirements for a Mac to run Silverlight 4+ are Intel-based 1.83 GHz (or higher) processor, running Apple's OS X Tiger (version 10.4.11+ or later) operating system with at least 512-MB of RAM, and a current version of the Safari or Firefox browser (click "Download Microsoft Silverlight" or select in the Related Articles at the end of this web page).  Silverlight 5+ requires OS X Leopard 10.5.7+ or later.

If your Mac is running "Mavericks" OS X 10.9 or later, follow the steps to use Safari Plug-in Manager (above) to allow the Silverlight plug-in to run in unrestricted mode specifically on CTI’s website for your MLS. 

For steps to fix Silverlight in older (non-Intel processor) Mac Power-PCs, click "Silverlight for Mac is not being recognized or you are continually prompted to install". To determine the version of your Apple OS and its processor, click on the Apple icon in the top menu and select "About This Mac."

Otherwise, to try fixing Silverlight problems in Safari yourself (see note 3 disclaimer below), progressively implement each of the following steps until the problem is resolved. For Firefox, see just step 1 and step 6. For Chrome, see step 1.  

  1. Close all your browser screens (Safari and any other browsers).
    • Re-open your browser and use it to verify which version of Silverlight is installed either by clicking on the "Verify Installed Version of Silverlight" link, or
      • in Safari: verify that Silverlight is recognized as installed by selecting Help > "Installed Plug-ins"
      • in Firefox: verify the version and status of Silverlight by selecting Tools > Add-ons > Plugins and ensure it is set to "Always Activate".
      • in Chrome: type "chrome://plugins" in the browser URL/Search omnibox, scroll to Silverlight, verify or click "Enable"; and also check "Always allow"
    • Un-install any version of Silverlight earlier than version 4  (i.e., uninstall version 1, 2 or 3 if listed). 
      • Note. While version 5 is the current version and is normally preferred, if it is not working correctly in your browser (especially in Chrome), you may try replacing it with version 4 if that version is still available. (See "Uninstall Silverlight on Apple Mac" above, or step 4 below.)
    • Re-open your browser and try to log into CTI Navigator Web again. 
  2. Open Safari's Menu (click on the gear icon if Menu is hidden) and select Preferences and then the Security tab:
    • verify "Enable JavaScript" is checked
    • un-check "Block pop-up windows" (under the Edit menu in older versions of Safari)
    • verify "Allow Plug-ins" (or Enable plug-ins) is checked
    •  If you changed any one of these settings, try to log into CTI Navigator Web again. 
  3. Remove Cookies and other website data in Safari:
    1. Click the word Safari in the browser's top menu and select Preferences...
    2. In Safari 7 select the Privacy tab
    3. Either click the "Remove All Website Data" button, or, to select and remove data for a specific website , click the Details button, select the specific website (such as, and click the Remove button 
    4. Close Safari and then re-open the browser. 
  4. Reset Safari to its original defaults by clicking Safari in the browser menu, selecting "Reset Safari..". (click here for details), and un-check any items you do not wish to remove.
  5. If the Silverlight error persists, un-install Silverlight (see un-install details above or summary below): 

    • Close all browser screens
    • Open Finder and browse to the hard drive where Silverlight is installed
    • Select/Open Library > select/open Internet Plug-ins
    • Click on the Silverlight.plugin and drag to Trash
    • If displayed, also click on "WPFe.plugin" and drag to Trash
    • Empty Trash! (You may need to restart your computer to ensure that all file components are removed.)

    Uninstall note: It’s very important that all Silverlight components are completely removed from your computer.  If you encounter difficulty uninstalling Silverlight on a Mac, you might run a free Mac app removal utility such as FreeMacSoft's AppCleaner (see Download Free AppCleaner for Mac in the Related Articles at the end of this web page), and delete the appropriate installed components found by the app removal utility. Otherwise, contact a Mac specialist either at Apple (phone 800-275-2273) or the national Tech Helpline for your state Association of Realtors (407-587-1450 for FAR members and 877-573-5611 for GAR members).

  6. Re-install Silverlight (see "Install Silverlight in Mac" above). Then try to log into CTI Navigator Web again. 
  7. If Safari on your computer still will not support the Silverlight plug-in, download and install a current version of Mozilla Firefox (or, in Windows but not Mac, install Google Chrome).
  8. If Firefox or its extensions do not function properly, follow the steps described in the MozillaZine article "Refresh Firefox - Reset add-ons and Settings"; and if necessary, "Standard Diagnositic - Firefox".

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Fix Error 4001 in Firefox on Windows

If you incur error 4001 when using Navigator Web in Firefox on Windows, but not when using Internet Explorer, then:
  1. Go to Start > Control Panel > Internet Options.
  2. Click the Connections tab, and then the LAN Settings button at the bottom.
  3. Un-check (to clear) the box labeled "Automatically detect settings".
  4. Click OK, then Apply and OK.

Run Silverlight in 64-bit version of Firefox (4+) on Mac OSX

To run Silverlight in a 64-bit version of Firefox (ver.4+) on an Apple OS X, ensure that the version of Silverlight on your computer is at least 4.0.60129.0 or later. See the appropriate sections above to verify, uninstall or re-install Silverlight. 

By default, Firefox 4 (and later) runs in 64-bit mode. According to Mozilla support (the provider of Firefox), you can set Firefox on a Mac OS 10.6 and later to run in 32-bit mode (if needed) as follows: 

  1. Select Firefox on the menu bar, and then select Quit Firefox. 
  2. Open the Applications folder in Finder and locate the Firefox application icon Firefox icon small.
  3. Hold down the Command key while you click the Firefox icon (or click on the "Perform task..." gear icon in the top menu) and select "Get Info" from the list of menu items.
  4. In the "Firefox Info" window, click the box in front of "Open in 32-bit mode".
  5. Close the "Firefox Info" window and then restart Firefox 4.

Note 3 - Disclaimer. Please be advised that CTI does not accept any responsibility for software you download, or for information provided about settings or software not produced by CTI (for details, see "CTI Disclaimers" in the Related Articles below).

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