I tried again at lunch time today as I had several new contacts to upload. Same first error msg but this time when I clicked "cancel" I got this screen:
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and this time it crashed to the point that logic needed to be clean and run as "fist time" when I restarted it.
The LoTW screen that loads is in ie not chrome.
I immediately switched to the old vista machine and the data uploaded fine with no errors.
Is there a known issue with win 8.1??? I have all updates loaded from MS and again have nothing else on the machine running in the background.