Quickbooks error 6144, 304 occurs because of the corruption in the company file. Error 6144, 304 directly impacts the company file. Causes: Improper shutdown of the system. Virus attack. Damaged company file. How Quickbooks error 6144, 304 can be resolved? Method 1: Through Quickbooks file doctor tool. You need to run the Quickbooks file doctor tool and it will scan the affected company file....