I did get it working yet, quite unfortunately, I don't know what the fix was. I am thrilled it is working but frustrated that I don't know the fix (I am an IT professional and recorded every troubleshooting step along the way, which resulted in a 1,100 Word document, but it started working between attempted launches without a record of a change). My struggles related not only to the Internet Explorer error but also to a 1603 error during installation and a 6123 opening my qbw file. Quite curious to me is that I was receiving the error with the most recent build when the "Use our built-in browser in QuickBooks Desktop" page implies that IE is no longer used. Thanks for the posts and sympathy; I'm moving on...
