Solution after finding myself unable to print multiple lines on my Quickbooks Invoices. Seems like there are a lot of other people who posted similar problems and Intuit was fairly unresponsive. (Here's a similar one) Hopefully this video will help shed some light on the issue. I almost wound up typing an amount and hourly rate for EVERY line on my invoices, even though only 1 line per invoice was actually required. Yikes!