Hi there, @Secret456.

You can find the QuickBooks Desktop (QBDT) manual you need from this article: Get QuickBooks Desktop user guides. Simply go to the See user guides section and choose QuickBooks 2016: The Missing Manual. Once opened, you can save the file on your hard drive. 

Also, you can always visit our Community help page to look for articles you can bookmark for future use. Simply, enter a keyword of your concern on the search box or select any of the categories displayed.

Should you need any assistance with accessing your QBDT account, please leave a reply below. I'm always available to help at any time. Take care.