I'm adding to this thread even though my question is about Quickbooks Desktop 2017 - because I can't seem to create a new question.

I want to have invoices show hours:minutes, and to be able to enter the same way (by manually entering information from a different time tracking system). I only have one client who wants this information on invoices, and they've only asked for this recently.

The time format in Preferences | General | Time Format shows Hours:Minutes, as stated in https://community.intuit.com/articles/1762948-entering-time-in-quickbooks-desktop-payroll-changes-to... I have not changed this setting.  It was only by reading the article that I found the setting. 

I am unable to enter the time on an invoice in hours:minute format even though the setting seems to be correct.  I'm still calculating the decimal hours, which is slow and inconvenient.

Thanks

Mike