One of the premier accounting software, QuickBooks is used by small and medium sized businesses for their basic to advanced accounting needs. Offering a great variety of tools, QuickBooks helps organizations in preparing invoices, bills, payments, managing payroll and many other things. All these features make QuickBooks the most sought after. But it is prone to bugs and errors which may disturb the process and ultimately the workflow. One needs to be aware and alert when the error occurs, so that they can resolved without any data loss.

QuickBooks Error 4120 is one such error which displays a message-

‘QuickBooks has encountered a problem and needs to be shut down for any further explanation’.

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What Causes QuickBooks Error Code 4120?
There are a series of reasons that can cause this error:

If any software change has occurred to QuickBooks, then the windows register has been corrupted.
When the QuickBooks executable file or other components are maked as unsafe by any anti-virus or security software.
When virus on your system harms the files that are related to Windows. This also poses a threat to QuickBooks related files.
When the files of QuickBooks are deleted by some program by mistake.
When QuickBooks is incompletely installed or there is some defective or corrupt download.