QuickBooks Error 6000 takes place when you are trying to open a company file. It can trouble you because of several reasons. The firewall might be creating an obstacle in the connection or the .tlg file is not valid.
It could also show up if the QuickBooks installation file is corrupted or there are a number of users who have signed in to the same company file.
You can fix it by configuring your antivirus software by referring to the steps mentioned below:
· Open the QuickBooks database manager
· Search for the port monitor option and then the QuickBooks version
· Take down the firewall port number somewhere and then open Windows Firewall
· Go to the advanced settings and right click on ‘Inbounds’ and then select ‘New Rule’
· Click on the port, fill in the number and then hit ‘next’
This should help you to get rid of the QuickBooks Error code 6000.

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