Remove extra spaces after the company name and before the company file extension. To do this, close QuickBooks and open the folder where the file is saved. Right-click on it and click Rename. Once done, check if you can open the file.
Re: I am unable to backup- "QuickBooks couldn't open your company file. error code -6143, -301
Let's check if the file's location is the reason of this error, cartforestry.
On your File Explorer, locate where you save your company file. Right-click on it and select Copy. Choose any location, right-click and click Paste. Right-click again and select Rename to give it a new file name. Once done, let's restore the copied file to see if it works fine.
In addition, it's best to reach out to our Customer Support Team if you're still getting the same error. We have a dedicated team that can fix file issues so you can open it as soon as possible.
Go to Help menu and select QuickBooks Desktop Help.
Click on Contact us. Enter the error code -6143, -301 in the question field.
Select Let's talk. Choose either Get a callback or Start a message.
Please comment again if you need more clarifications. I'll be here to help.
Open your data file on trial license of Pro 2020. If the error code is the same one, your data file may be damaged. Call and ask Intuit Data Service to fix it. Should you need to resolve it in due course, consider purchasing a 3rd party file repair service.