QuickBooks Company File is Used by Another Application

QuickBooks is very helpful for business owners who want to manage business accounts by using advanced features of this accounting software. It is a perfect solution for small and medium-sized business accounts because you can find very helpful features to store business information and data with it. It can be easily used to store the complete information of your business employees, vendors, clients, customers, products, and business transactions. All this data is stored in your company data file of the QuickBooks system.

QuickBooks Company File is Used by Another Application

When you are using this accounting tool for your business, you never want to face any error with your company file. But there can be various errors due to different reasons. There is a common problem when users face the issue that the QuickBooks company file is used by another application. It is a very serious problem and it can be in form of Error: 6144 or 301.

Related Post: QuickBooks Error Code 6144, 304   

Here are some common reasons for this issue in your QuickBooks company file:

  • QuickBooks installation is corrupted
  • A computer that is not the server is hosting the company file
  • Incorrect network setup
  • The mismatch between the transaction log file (.tlg) and the company file (.qbw)
  • The company file is damaged
  • This error occurs when opening the file locally

These are some of the common causes when you face such a problem with your QuickBooks company file. There can be many more reasons for it. You have to find a solution according to the reason for this issue. If you are also looking to find a solution to this issue, you can use the following processes it:

  • Download and run the QuickBooks file doctor tool for automatic resolution of the problem.
  • Use auto data recovery solution to find your data back in the company file
  • Find if there is any other application using QuickBooks in task manager
  • Check for the latest update of QuickBooks
  • Restore the previous backup of the company data file
  • Try to find the solution manually according to the cause of the problem

Four Solutions of error when QuickBooks company file is used by another application

Solution 1: Switching to multi-user mode

  • Go to the Taskbar and check whether the company file is opened or closed.
  • Now, check if the company file is opened in which modes like multi-user mode and single-user mode by the users.
  • Finally, get the machine where a company is open in single-user mode, go to file, and change the mode to multi-user mode.

Method 2: Steps to follow if the data file is located on the server

  • Close all the instances of the QuickBooks running on every machine
  • Now go to Server computer, press Ctrl +Alt + Del button together to get the task manager open.
  • Select the task manager option
  • Go to Process tab available
  • In the process tab checkmark the option “Show processes for all the users”
  • In the process list search for mysqld.exe.
  • Select the process mysqld.exe and then click on End Process
  • For the QuickBooks 2013 and older versions, the process will be shown as mysqld-nt.exe
  • Open the folder which contains the SAJ company file
  • Locate the process.PID and delete it
  • Now check if the issue has been resolved, if not reboot the server

Related Post: QuickBooks error code 301   

Method 3: When a data file is available on the server however you are not able to access it

  • Open the Explorer
  • Now copy the SAI and SAJ from the server and copy them to the desktop temporarily
  • Go to the desktop and open the company file
  • If for any reason you are unable to open the company file, then allow the server to restore the latest backup.
  • If the file is not opened then verify that it is not opened
  • Wait till you access the server
  • After getting access to the server, reboot the server
  • Paste the SAI and SAJ file from the Desktop to the server and overwrite it
  • Finally, you need to delete the Desktop file

Method 4: Data is available in My Documents but it is redirected to the server and Process.PID is not available inside the SAJ folder.

  • Copy the SAI and SAJ folder the C drive of the computer
  • If the file is opening to any new location, then save the file to my documents with a new name (My documents is its original location)
  • Don’t forget to delete the.SAJ folder

These are some of the common factors that you can consider when you want to solve QuickBooks Company File is Used by Another Application problem in your QuickBooks system. If you are unable to find the solution to this problem, you can also get help with services of professional support service providers. They can provide Online technical support solutions to solve this issue in your QuickBooks system. You can contact them to find the solution to this error in your QuickBooks company file.

You can even contact our Quickbooks Customer Service and you can Chat with our QuickBooks technical expert.

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  1. If another user is doing something then also I get the error QuickBooks company file used by another application?

    Yes, you get the error as the user is doing the task that allows one user at a time even in the Multi-user mode. So if you know who is using it then talk to them. If you don’t then start your task as another user finishes it.

  2. What if the error QuickBooks company file used by another application refers to a specific user?

    1. Firstly, close the QuickBooks and then open it again on the workstation where this error happens
    2. In another workstation, open the QuickBooks then click on the Company menu option. After that, select the Users and then click on the View Users option
    3. If the specific user is no longer signed in then go back to the user’s list. Now you can do your work without any errors.

  3. Is this error QuickBooks company file used by another application happen in multi-user mode only?

    No, this error can happen in both Single-user and multi-user modes. You have to wait and try these things:-

    1. Fix the QuickBooks performance problems by managing the computers
    2. You can also manage the data files to manage the performance of QuickBooks.

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