This is maddening. Intuit costs me time and money every time a customer walks away without paying because I can't open QBO. Intuit employees clearly do not read the string. The same useless information abut 2-factor authentication has been pasted into this thread over and over.
READ THIS, INTUIT: I want multi-factor authentication turned off entirely. Anyone who wants 2-factor can always turn it on.
If you post that BS about turning off 2-factor authentication again, I will flame you unmercifully.
