How to fix QuickBooks Error 80040408 - Could not Start?
                     What is QuickBooks Error 
80040408 and How to fix 
it?
QuickBooks Error 80040408 is an outcome of improper settings and 
configuration of QuickBooks during a multi-user environment. The 
error message shows up as Begin Session Error Code: 80040408 
couldn't start QuickBooks. Troubleshooting this error may be a tricky 
process, and a user might fail to resolve this issue even after following 
all the troubleshooting steps.
Possible Causes behind QuickBooks Error Code 
80040408:
Error: 80040408 may result because of multi-faceted technical factors, 
you'll find within the below-given list:
•    When the QuickStart option has enabled in QuickBooks software
•    QuickBooks is already getting used within the single-user mode 
causing QuickBooks Desktop error 80040408
•    When the QuickBooks file name has changed and becomes 
available to a separate file
•    When the QuickBooks file has moved from its original location, 
and also the path of the file has now changed from
•    What you set up within the QQube Configuration device
•    QuickBooks is open to a particular company file before trying to 
load multiple company files
•    The QuickBooks is unable to run within the multi-user 
environment because the dedicated network user has logged out
•    QuickBooks has currently utilized by a similar QuickBooks QQube 
user configured to attach to the QuickBooks
•    Multiple cases of QQube Synchronizer moving on the server or 
workstation
Important: Check the points given below before proceeding 
further with the troubleshooting steps
•    Confirm that the QuickBooks Quick Start option has turned off.
•    No other user should be utilizing Single User mode.
•    Make sure that the server is running.
•    Make sure that QuickBooks hasn't set up to open a specific 
company file avoiding it to open multiple files.
•    Ensure that the location of the company file is correct in 
QuickBooks and you've got not moved your company file to a 
distinct location on your computer.
• Verify the name that you just have chosen for the company file 
in QuickBooks matches the name of the company on the file 
on your computer.
How to Resolve QuickBooks Error 80040408?
After knowing the possible causes of the error, let's proceed with some 
general troubleshooting solutions to resolve Intuit QB Error Code 
80040408:
Solution 1: close up Quick Start Option
To disable the QuickStart feature in QuickBooks, you require 
navigating through the general tab and clicking on My Preferences. 
Now locate Quick Startups and un-check the box against an 
equivalent. If an equivalent error remains unfixed, try the next 
troubleshooting solution.
Solution 2: Sign out All Other Users from QuickBooks
QuickBooks error 80040408 may be triggered when another user 
within the program is performing an administrative task on a remote 
system. During this case, logging out all the users from the QuickBooks 
program can resolve the issue.
Solution 3: Modify Settings on QQube Configuration Tool on 
Window
To get the task done, follow the below-given steps:
•    Go to the QQube Configuration Tool window
•    Click on Database from under Advanced Options then hit the Show 
More button
•    Now tick the boxes against Synchronizer and Database Manager 
Options
Note: Attempt to perform an equivalent step giving the error code 
after applying every single troubleshooting solution then move to 
subsequent one if the QB Begin Session Failed Error = 80040408 
continues.
Solution 4: Change the name of QuickBooks Company File to 
Its
Original One
When the name of the company files is modified, you'll modify the 
name of your company file, as listed earlier within the QQube 
Configuration Tool. Alternatively, you'll remove the company file to 
rename it back to the first. It's impossible to get it done directly from 
the QQube configuration tool.
You require having a multi-user version where you'll perform the 
renaming on the server. Try the succeeding method if unable to open 
QuickBooks error 80040408 continues troubling you.
Solution 5: Replace the original Path of the File
QB doesn't Start Error 80040408 may cause because of the change 
within the company file path when someone moves it from its original 
location. During this scenario, you have required the different locations 
of the company file by utilizing the QQube Configuration Tool.
Still, if your issue hasn't resolve then don't worry this can common as 
we described earlier at the start of this post that it has complicated to 
repair this error, and even after applying suggested fixes.