Way 1: Uninstall the Antivirus Program and Rename the QB folder

After performing all the above solutions, if the error does not get resolved then the issue may present in the antivirus. So, we try to configure it with the step-by-step process.
- Start the process by holding CTRL + Shift + Esc to open the task manager.
- Secondly, visit the processes tab and then try to spot the antivirus installed in the system. For instance: Spy Sweeper
- After spotting it, just click on it and choose the end process.
If the user is getting any kind of issue while doing this task then make sure to uninstall the antivirus application.
Now, it’s time to rename the Quickbooks update folder that the user can do with these steps:
- Conduct the operation by pressing the Windows + E button together and opening the file explorer.
- And then navigate to the C:/ProgramFiles\Intuit\Quickbooks(year)\Components. 
- In this step, perform a right-click on the downloadable folder.
- And choose the rename option.
- Moving ahead, try to add .old to the end of the name.
- In the last part, just update the Quickbooks desktop again and enjoy the smooth working within the software.
- The user needs to take into account that the XX in downloadable denotes the year of the version of the Quickbooks. So, don’t get confused with it.

Way 2: Disable User Account Control

If the above solution did not provide you success in resolving the error issue. Then, try to disable the User Account Control by performing the steps given below.
Steps to modify the user account control settings for windows 10, 8.1, 8, and 17.
- The first thing that you need to do is to access the run box.
- Then, go in for the control panel in the dialog vox.
- After that choose the user accounts option.
- Moving on, tap on the change user account control settings.

Regards
willjoe

Different errors that occur in Quickbooks have different reasons. The QuickBooks error – 6123 may occur due to one of the following issues
- A port is being blocked by your system’s firewall, which is needed to communicate with the server hosting the company file
- Quickbooks system files are damaged / QWB files are damaged
- Data related to the Quickbook is corrupted
- Program files related to the Quickbooks is damaged or corrupted
- Multiple Quickbooks databases are running on your system
- The company file you are trying to access is open in another newer version of QuickBooks software

Method 1: Using Quickbooks connection diagnostic tool

This is an easy method and all you have to do is, install and run Quickbooks Connection Diagnostic Tool.
- On your main System, the Host PC, check my network connection
- Install the Quickbooks Connection Diagnostic Tool
- Follow the steps, and once the process is finished try opening the Quickbooks this might solve the connection error most probably.

Method 2: Fixing the damaged data file

- Navigate To the start menu, open it and click explore
- Check your company file and press right-click on the company file having ‘.ND’ extension
- Rename the file from ‘YourCompanyFile.nd’ to ‘YourCompanyFile.ndold’
- To switch to multiple user mode, you will have to follow the below-mentioned points
- Navigate to the ‘File’ menu option
- Locate the ‘Utilities’ tab under it
- Once you click on it, another drop-down menu will appear
- In the menu under the utilities, click on ‘Host Multi-user access’
- Next, Go to the ‘File’ menu tab
- Under the file menu, click on ‘Switch to Multi-User Mode.’

Regards,
Willjoe

The following are the causes of the QuickBooks error 176104:

• “Entitlement Client Data files” have been compromised.
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• The server copy of the POS program is not registered.
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• As it is being run for the first time, the user copy of the POS framework has been started before the “server copy of POS.”
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• A faulty or ineffective point-of-sale system.
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• One or more POS files are being blocked or restricted by the firewall.
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• It’s possible that the device would have “network synchronization problems.”
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The following are the methods to troubleshoot QuickBooks error 176104:
Method 1: Update the POS to the most recent version.

• On the update page, choose “exit.”
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• Pick Help “check for software” from the drop-down menu.
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• Allow time for the POS to be modified.
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• Choose “Registration” from the “Help” menu. Register “Point of Sale” here.
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• Reopen the “Client copy of POS” after starting the “Server copy of POS.”
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• To open a search window, tap “Windows + R.”
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• Type “services.MSC” into the search box.
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• To access the service, look for “vxx” and double-click it.
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• If the service appears to have ended, click “start” to change the status to “started.”
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• If the program is already working, press “stop” and then “start” to restart it.
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• Close the window by pressing OK.
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• Restart the POS software. Now reopen the POS.
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