Looks like that was a problem early on LAST YEAR. https://proconnect.intuit.com/community/lacerte-tax-discussions/discussion/k1-export/00/47372
Patience may be your only solution, or spend hours with support to get "I don't know"
Maybe @IntuitAustin could get someone to report back as to whether this is a known unexpected behavior.
Anyone else still having this issue? We have narrowed it down to an issue with Windows 10 but still no support from Intuit.
2 Windows 8.1 machines work perfectly for any year and user.
4 Windows 10 machines are sporadic. Will work sometimes but usually get the "K-1 indexing file is currently in use" error - even when that same user can login the 8.1 machines and export it immediately after.