Firefox is one of the commonly known and popular web browsers after Google Chrome. Mozilla releases its web browser updates regularly and sometimes after the upgrade it also becomes incompatible with the operating systems. This is mainly due to its newly added features or due to some pre-installed programs.
The most irritating message that appears in such a situation is “Couldn’t load XPCOM”
You might have tried to fix this error by running various virus scans, removing junk files by clearing cache and also performing a system reboot. But you may have noticed that none of these attempts is helpful while fixing the error.
In this article, I will provide you with the causes and solutions of this error and I will provide you with some effective methods that will prove very helpful to solve this error.
Every operating system may use a separate solution to the problem I have tried my best to list them here.
- 1 Causes Of FireFox XPCOM Error
- 2 How to Fix Couldn’t Load XPCOM Error
- 2.1 1. Fix Couldn’t Load XPCOM error in ThinderBird
- 2.2 2. Fix Couldn’t Load XPCOM Error in Tor Bundle Browser
- 2.3 3. Fix Couldn’t Load XPCOM Error In Windows
- 2.4 Run TDSSKiller Anti-rootkit utility
- 2.5 Delete malicious entries from Windows Startup
- 2.6 Uninstall Unknown or Unwanted programs
- 2.7 Reset your Firefox Browser Settings
- 2.8 Step-by-Step Guide
- 2.9 FAQ
Causes Of FireFox XPCOM Error
The XPCOM error may occur due to the following reasons:
- There are chances that you may encounter this error in Windows OS based computer. It usually occurs when a user updates the Windows and then opens Mozilla Firefox frequently.
- This error also occurs if the Firefox’s profile folder id corrupted l. Firefox’s profile folder corruption usually occurs due to a virus attack or after installing a third-party extension on the Firefox browser.
How to Fix Couldn’t Load XPCOM Error
Now let’s discuss the methods to fix “Couldn’t Load XPCOM Error“.
1. Fix Couldn’t Load XPCOM error in ThinderBird
Thunderbird programs and ThunderBird profile folders are not stored in the same place. So you can uninstall Thunderbird and then reinstall a new and updated version without any adverse effects on emails and downloads etc.
To uninstall the program follow the steps below:
Step – 1: Go to Start and then select Settings.
Step – 2: Now go to the control panel and select ‘Programs and Features’.
Step – 3: Now select Mozilla Thunderbird and then click on the uninstall button.
2. Fix Couldn’t Load XPCOM Error in Tor Bundle Browser
If the XPCOM error appears when you open the Tor Browser Bundle, that is because Webroot security software was preventing Tor from irritating.
Though you don’t have to delete your webroot security software package. Just follow these simple steps below:
Step – 1: Open Webroot and then click on Identity Protection.
Step – 2: Find that file which contains the word ‘tor’ in c:\users\desktop\torbrowser\browser’
Step – 3: Now on the right side you will find the following options: protect, allow, deny
Step – 4: Select ‘allow’ from these options.
Now this will fix the XPCOM problem in Tor Bundle Browsers.
3. Fix Couldn’t Load XPCOM Error In Windows
Run an Anti-virus through the system
The precautionary measure to ensure before resolving the XPCOM Firefox problem is to make sure that if your computer is free of malware or viruses.
First of all, Boot your computer into Safe Mode
For Windows 7, Vista and XP
Step – 1: Restart your computer and press the F8 key before the Windows logo appear
Step – 2: The advanced options menu appears on the screen to SafeMode with networking option and then press enter.
For Windows 10, 8.1 and 8
Step – 1: Press Windows + R keys to open the RUN window.
Step – 2: Now type misconfig and select OK.
Step – 3: Go to the Boot tab
Step – 4: Now choose the Safe Boot and Network Options and then select OK.
Step – 5: Now restart your computer.
Run TDSSKiller Anti-rootkit utility
Step – 1: Download Kaspersky’s TDDSSKiller Anti-rootkit utility in your computer.
Step – 2: Run TDDSS Killer
Step – 3: Accept the License agreement
Step – 4: Now tap on Next.
Step – 5: Use the Smart Scan button and wait until the scan is finished.
Step – 6: Now select the “Cure” to remove the errors (if found).
Delete malicious entries from Windows Startup
Step – 1: First of all, download and Install CCleaner
Step – 2: Run CCleaner utility
Step – 3: Now select Tools
Step – 4: Tap on the Startup button
Step – 5: Choose the Windows tab
Step – 6: Select and delete any suspicious entry that is listed there.
Uninstall Unknown or Unwanted programs
Step – 1: Open Windows Control Panel.
Step – 2: From the programs list find and remove any unknown or unwanted application that is listed here.
Reset your Firefox Browser Settings
This step is optional you can apply it if you want to. If the XPCOM error still occurs then make sure that all the useless plugins, extensions, and settings were removed from the browser when the above steps were performed.
Just follow the steps given below:
Step – 1: From Mozilla Firefox’s menu icon choose Help.
Step – 2: Select troubleshooting information.
Step – 3: Now click the Refresh Firefox button.
Step – 4: Select Reset Firefox again
Step – 5: Close all open Firefox windows.
If the XPCOM error persists imply of any methods enlisted below for an error-ridden Firefox browsing experience.
Run the Firefox installer and follow the on-screen instructions to repair and upgrade the current Firefox application. You can get the latest version of firefox from the internet.
Uninstall Firefox completely and then re-install it
If the above option didn’t prove beneficial for you then try following this one.
Complete uninstall means that you need to remove everything related to Firefox from your computer like:
- Uninstall Firefox
- Remove Registry Entries
- Remove from program files
- Delete Entries from AppData folder
- Delete entries from the Program Data folder
It is recommended that tempering with the registry editor because the wrong registry keys may lead to other complications.
What causes the XPCOM error?
The XPCOM error may be caused on a Windows-based computer whenever a user tries to open Mozilla Firefox after a Windows update or if Firefox’s profile folder is corrupted.
What is the file XPCOM?
XPCOM.dll is a type of DLL file associated with Firefox which is developed by Mozilla Foundation of the Windows operating system. The latest known version of XPCOM.dll is 17.0.6, which is produced for Windows. This DLL file carries a popularity rating of 2 stars.
What do you do when Firefox won’t open?
- Find the firefox.exe program file in the Firefox application folder on your system.
- Right-click on the icon.
- Select Run As Administrator
- The firefox application is started using the administrator Windows account.