I have contacted tech support three times with this issue. Nothing has changed. I have used the import utility for many years saving hundreds of hours of keyboard time.
I hope someone from Intuit reads this message board and gets on the ball to get this issue fixed.
I have solved this issue on my own. ProSeries has never gotten back to me with the fix. And previously told me it was not a ProSeries issue but a QB one. It is not.
However, each morning I make sure the ProSeries updates are installed. Secondly, I check Windows 10, I have found that due to many issues Windows 10 updates are not always run automatically. Try checking Windows to make sure you have the most update to date version. After doing this I have been able to import into ProSeries. Hope this helps you.