QuickBooks Error code 4120

Resolve QuickBooks Error 4120 in 7 Easy Methods (Updated)

You’ve been using QuickBooks for your business for years now, and you’re pretty comfortable with it. But today, you encountered a new error message that you’ve never seen before: QuickBooks Error 4120. You did some research online, but all the articles seem to be outdated or not applicable to your situation. So what do you do?

Well, we are here to help. Below are the troubleshooting steps that we’ve found work best for resolving the QuickBooks Error 4120. But before we get started, we should explain a little bit about what this error is.

What is QuickBooks Error 4120?

QuickBooks Error 4120 flashes on your screen while you are performing various tasks on the application. When your operating system is corrupted then you will face this error. You need to fix this type of error so that it cannot affect your other tasks. Now we will look at the causes to understand it better. Moreover, an error message pops up quoting “QuickBooks has encountered a problem and needs to be shut down for any further explanation”.

QuickBooks error code 4120: error message

Causes of QuickBooks Error Code 4120

Follow the below-mentioned steps to identify the QuickBooks error code 4120:-

  • If you make changes in the software that occurred to QuickBooks the windows register may be corrupted
  • When the anti-virus or security application marked any QuickBooks executable file or other unsafe. 
  • When windows related files are harmed by a virus on your system. This also poses threat to QuickBooks. 
  • By mistake, if the files of QuickBooks are deleted by another program. 
  • If QuickBooks installation is not proper or may there be some corrupted downloads. 

Symptoms of QuickBooks Error 4120 

  • Software start working slowly and the mouse and keyboard inputs are responded to sluggishly. 
  • Your system may crash due to the occurrence of an error code. 
  • Your system may also freeze. 
  • Windows operating system crashed while working. 

System Requirements to Avoid Error 4120:

There are some basic requirements that to be fulfilled. When the requirements are not met then it causes errors in your QuickBooks software. Below are the following requirements:-

  • Operating system:- Windows XP, Windows Vista, Windows 7, Windows 8, and more. 
  • The processor is 2.0 GHz. 
  • RAM is 512 MB. 
  • Internet connection is required. 
  • The internet explorer browser is 6.0
  • The CD ROM is a 4x CD ROM drive. 
Also Read: QuickBooks Online vs QuickBooks Hosting

Methods to Resolve the QuickBooks Error 4120

There are some methods to follow to troubleshoot Error 4120 QuickBooks. Follow all the steps correctly:-

Method 1- Verify any System Error

Microsoft Security Essentials

  • You have to update the antivirus and anti-malware program
  • Then, start scanning your system when the program is activated. 
  • Now, remove the virus and resolve bugs. 
  • When you verify that the virus is not causing this error then move to the other method. 

Method 2- Copy Company File to Other Systems

  • Initially, you have to copy all company files to another system. Then, verify if you can open the file in another system or not. 
  • Now, if the file opens then repair the windows of the previous system. 
  • If your file is not able to open in any other system, it means the files are damaged. This can be repaired by using the QuickBooks File Doctor tool. 

Method 3- Install and Run QuickBooks File Doctor 


The QuickBooks file doctor tool is designed and developed to fix all company file-related issues. You can run and resolve to verify the errors and can get resolved automatically. 

  • Firstly, you have to install the QuickBooks file doctor tool
  • Then, run and diagnose to verify the error. 
  • Finally, remove the issue. 

You can also download the file doctor from the QuickBooks tool hub

Method 4- QuickBooks Reinstall and Repair

  • First of all, move to the Control Panel and then go to Uninstall QuickBooks.
  • Now, try to repair the software. 
  • Then, if you found any error then reinstall the QuickBooks

Method 5- Use Disk Cleanup


  • Firstly, you have to make sure to take a backup of the files and free up the space on a hard drive. 
  • Then, clean the cache and restart your system. 
  • Now, you can run the disk cleanup and go to the explorer window and click on the directory that is C:
  • Lastly, you have to click on the Properties option and tap on the disk cleanup. 

Method 6- Microsoft .Net Framework Repair and Reinstall

The steps are different for the versions of windows. Follow the steps in order to resolve the error in an easy way:

For Windows 7, Vista, XP
  • Initially, you have to close all the background running applications. 
  • Then, go to the Windows start menu
  • Now, move to the control panel and also the add and remove option. 
  • Go to the Microsoft .Net Framework 4 extended. 
  • Also, click on the Change/uninstall and also remove and repair. 
  • After that, set up wizard windows that will display on your screen. 
  • Now, select the repair option and click on next. 
  • Then, you have to perform the wizard for repairing .Net framework installations
  • Lastly, you have to restart your system. 
For Windows 8 and 10

The Microsoft .Net framework 4 is in the programs and features tab. The .Net framework 4.0 is part of the Windows 8 operating system as a feature. To resolve the issue you can use the Microsoft .Net framework repair. 

Method 7- Windows update Download

Windows Update

When windows updates are installed on your system then you can install any missing fixes for the .Net framework, MSXML, and C++ issues. If the operating system is not updated then the software is not able to install or open correctly. Follow the below steps:-

  • Firstly, go and click on the windows start option. 
  • Then, enter windows update from the search box. 
  • Now, reboot your system when the update installation is done. 

Other Ways to Resolve

  • You can clean out junk and trash file from the system. 
  • Repair registry entries that are related to the errors. 
  • You can use the Windows System Restore so that you can undo the changes you made to the system.  
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Winding Up!

All the above-mentioned Troubleshooting Steps to Resolve QuickBooks Error code 4120 will be helpful for you and may fix this error from your system. We discuss all the essential topics that help you to understand error 4120 QuickBooks. If you face any other issues or errors then check out our other posts also to resolve them. 

Frequently Asked Questions (FAQs)

Q1. How do I fix error 4120 in QuickBooks?

Follow these steps to fix QuickBooks error 4120:

  • Reinstall QuickBooks.
  • Use QuickBooks File Doctor Tool.
  • Paste Company Files to another PC.

Q2. How do I fix a script error in QuickBooks?

By following the methods you can fix script error in QuickBooks:

  • Clear all Cache Data.
  • Disable Add-ons in internet explorer.
  • Deselect SSL certificate from Internet Explorer.
  • Add Intuit to your trusted website.

Q3. How do I fix error 3140 in QuickBooks?

To fix QuickBooks error 3140 follow these instructions:

  • Make sure QuickBooks is running in Single user mode.
  • Use Rebuild Data Utility.
  • Remove all Junk files.
  • Install the Latest Update of the Windows.