QB Desktop error message 6144, 301

Can you open the sample file?

Yes I just tried. It says you are opening a file that has the unit of measure feature turned on. Because this feature is not available in you edition of Quickbooks, you will be able to view and use existing units of measure, but you will not be able to create new ones or change existing ones. 

As long as you can open the sample file, your QuickBooks is running well. It is highly possible your primary file is damaged. You need to purchase a 3rd party file repair service.

Welcome to the Community, @TB47. 

In addition to Fiat Lux's suggestions, we can also perform some troubleshooting steps to get rid of the error. 

Let's start with restoring a back up or a portable copy of your company file and check to see if you can access it without error. Before doing so, I recommend copying the backup or portable files locally. 

However, if the same error persists, you can also use the Auto Data Recovery tool. This will help you to recover lost or corrupted files.

For your reference about the process of fixing the error, please visit this link: Error -6144, -301. 

I've also got here a compilation of help articles that can further guide you in completing your QuickBooks tasks. Feel free to open them whenever needed. 

I'm always around the corner if you need further help in accessing your company file. Just post a reply below and I'll circle back to help you out. Have a great day ahead.