How To

Fix “Couldn’t Load XPCOM” Firefox Error – 5 Ways [Step By Step]

Are you getting a Couldn’t load XPCOM error in Firefox and don’t know what it is? The error pops up as a result of the incompatibility of the features of the web browser with Windows.

Mozilla comes up with regular updates for Firefox, but sometimes these updated features prove to be incompatible with the Operating system due to which the “Couldn’t load XPCOM” error occurs. But you can fix the error easily with some simple methods.

What is XPCOM in Mozilla?

XPCOM stands for Cross Platform Component Object Model. XPCOM makes the environment of the application like an actual framework. The software developer gets the following features from this development environment:

  • File abstraction
  • Component management
  • Memory management
  • Object message passing

While running your Mozilla Firefox, if you are facing the error related to XPCOM, then you are at the right page. Keep reading the article to gather more information about the topic.

What Causes “Couldn’t Load XPCOM” Firefox Error?

The main causes behind the “Couldn’t Load XPCOM” Firefox Error are:

  • Due to Windows update
  • Corrupt Firefox’s profile folder
  • Virus attack
  • Installation of third party extension 

How to Fix Couldn’t Load XPCOM Firefox Error?

The 5 working solutions to solve “Couldn’t load XPCOM” error are:

  • Method 1. Use Firefox in Safe Mode
  • Method 2. Re-installing Firefox
  • Method 3. Reset the Firefox Settings to Default
  • Method 4. Back Up and Get in the Clean Boot State
  • Method 5. Repair Corrupt Files

1. Solve Couldn’t load XPCOM using Firefox in Safe Mode 

The first method that you can try to fix the error is to open Mozilla Firefox in Safe Mode. For this, follow the given steps-

Step 1: Hold the shift key down and then to open the Mozilla Firefox application, double click it.

Step 2: Now select the Start in Safe Mode option.

Step 3: If the Firefox application starts without any error in Safe Mode then the Firefox extensions installed might be the reason behind the error. And so disable the installed Ad-on one after the other, close and restart Firefox normally. Follow these steps to discover the plugin leading to the problem.

To disable the extensions and Firefox plugins, follow the given steps.

Step 1: Click on the three horizontal lines at the top right corner of the home page. Then select Add-ons.

Step 2: Now disable the Add-ons installed from the Extensions pane. Then restart the application normally to discover the extension causing the error.

Step 3: After you get to know the root of the problem, it is advised that you remove the extension completely, provided you run the application in Safe Mode.

That’s it. After disabling the Add-ons and the extensions, check if the error still persists. If yes, then you can try the next method.

2. Solve XPCOM loading error by Re-installing Firefox

The next method that you can apply to fix Couldn’t load XPCOM Firefox error is uninstalling, reinstalling and then upgrading the web browser to the latest version. For this method, you will require another web browser like Internet explorer or Google Chrome.

Step 1: Firstly uninstall Mozilla Firefox completely from your device. Removal of the application means that you remove everything that was related to it. You can complete this step either from Registry Editor or take help of some uninstaller like Iobit.

  • Uninstall Firefox
  • Remove the Registry entries
  • Delete from Program files
  • Remove entries from the AppData folder
  • Removal from the Program data folder

Step 2: After uninstalling Mozilla Firefox, make sure you delete the Mozilla folder in the Roaming folder from AppData.

Step 3: Now download the latest version of Mozilla Firefox from web browser like Internet Explorer and install it on you device.

Now your web browser is all set to open and offer you its services without any kind of error. So you can browse anything very easily now.


3. Reset the Firefox Settings to Default to fix XPCOM error. 

Resetting all the Firefox settings to its default value is another tried method that helps to fix couldn’t load XPCOM in windows 10, 8.1, 8. These steps will help you complete the process.

Step 1: Open the Firefox application in Safe Mode.

Step 2: Now choose Refresh Firefox option.

Step 3: Then choose Refresh Firefox again.

Step 4: As you will refresh Firefox, all the settings will restore to its default. The add-ons will be removed and a new user Id will be created. But the following items are not removed by this feature-

  • Passwords
  • Bookmarks
  • Browsing History
  • Cookies
  • Personal Dictionary
  • Open windows and tabs
  • Web form auto-fill information

4. Back-Up and Get in the Clean Boot State

Another method to resolve the issue is getting the system into the Clean Boot State. And so by just carrying out this clean installation process, you can enjoy errorless browsing with Mozilla Firefox.

Step 1: Press the windows icon key +R together to open the Run dialogue box. Now type “msconfig” and run the command to system Configuration utility.

Step 2: Now in the General tab, select Selective Startup.

Step 3: Next click on the Services tab. And then select the check box against Hide all Microsoft Services. Click on the Disable All option.

Step 4: Now click on Apply and press Ok to save the changes.

Restart your device and check if Firefox is running without the error. But if the error still persists, then don’t worry. We still have one more method to fix the issue. Hope that it would be of some help to you guys.

5. Repair Corrupt Files to fix Couldn’t load XPCOM problem

If none of the above methods works for you, then you can try this last method. You should give a shot to this universal solution that can resolve almost every problem that comes up with Windows. Just download Reimage Plus and run the scan. All the corrupt files will be restored and repaired, fixing the issue.

You can get Reimage Plus from here.

We have tried to cover all the possible methods that will help you fix the couldn’t load XPCOM error. We hope that one of these would help you out of the situation. If you are still stuck with the error, please share your query with us in the comment section below.

About the author

Jeff Peterson

Jeff is a tech geek whose hobby is to learn about the latest developments in the tech world. When he is not writing at you may find him coding or playing his favorite video games