I followed the instructions outlined here:
https://www.quicken.com/support/error-106-324-168-or-999-when-downloading-quicken-mac/
After disconnecting the accounts, I closed Quicken before opening and trying to reconnect the accounts. I used the + icon to add new accounts, knowing that later it would allow me to link the accounts, but it wouldn't get that far. The error pops up immediately after the MFA.
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