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If your QuickBooks is also running slow then there is nothing to panic. This is a common problem. This problem can happen to anyone and you will be able to solve it very easily. Having this problem offline and online is both a different thing. Slow QuickBooks means lost production and visible time or there may be other reasons for this. Here I will give you some solutions and tips, with the help of which your problem will be solved.
Some types of QuickBooks performance issues
These are some of the main reasons, they can be understood by reading them.
QuickBooks doesn’t respond while opening a company file in multi-user mode.
POS got stuck while using QuickBooks Point of Sale.
QuickBooks Desktop freezes while entering transactions or exporting reports.
While updating, rebuilding, or backing up data, a blue circle continues to spin.
QuickBooks does not respond to any command.
Solutions to Boost up QuickBooks speed
Update QuickBooks Desktop Application
First you have to check whether your QuickBooks is updated to the latest version or not. If not, you will have to update. Because not updating can also be a big reason for slow speed.
Rename QBWUSER.INI File
Open Windows File Manager by pressing Windows + E keys on the desktop.
Navigate to C:\ ProgramData\ Intuit\ QuickBooks folder.
Make sure Windows is set to Display Windows Hidden Files.
Locate and right-click QBWUSER.INI file.
Select Rename and add .OLD at the end of the file name.
Save the file name and try to run QuickBooks Desktop once again.
If QuickBooks is still running slow, then follow the next troubleshooting step.

Verify the Windows System Configuration
Following is the minimum system requirement that needs to be fulfilled in order to run QuickBooks Desktop efficiently:
Core 2 Duo Intel processor 2.4 GHz minimum or any upgraded version.
4 Gigabytes of RAM.
5 Gigabytes of free disk space after installation.
Optical Drive or connectivity to the internet.
1280 x 1024 Screen resolution.
US version of Windows that must be either Windows 10, 8.1 or 7.
Installation on a server requires Windows Server 2016, 2012 R2, 2011, or 2008 R2 SP1.

Repair Damaged or Corrupt QuickBooks Company File
Run QuickBooks Verify or Rebuild Data Utility to repair damaged QuickBooks Desktop company files.
Verify Company File Size
Navigate to the QuickBooks company file folder and right-click the company file.
Select Properties and check the file size.
If you are using QuickBooks Pro and the company file size is more than 150 MB, then you need to use QuickBooks Condense Data Utility to reduce the file size.
The same implies when you are using QuickBooks Enterprise, and the company file size exceeds 1 GB.
To condense a company file, open QuickBooks and click the File tab.
Select Condense Data from under the Utilities section.
Put a checkmark next to the “Keep all transactions, but remove audit train info to date” option.
Click Next and wait until the “Your company file has been successfully condensed” message appears.
Click Close and run QuickBooks one again. In case QuickBooks is still loading slowly, then follow the next step.

Reinstall QuickBooks Desktop
Download QuickBooks Tool Hub from the official Intuit website to download the Tool Hub app.
Open the setup file from the downloads of your computer and follow the on-screen prompts to finish the installation.
Run QuickBooks Tool Hub from the desktop of your computer using the application icon.
Click the Program Installation Issues tab and click QuickBooks Clean Install Tool.
Run the tool to install a fresh copy of QuickBooks Desktop application.
Use QuickBooks Clean Install Tool and reinstall QuickBooks Desktop application on your Windows computer.

Repair or Reinstall Windows Operating System
Lastly, repair your operating system and install it again.