This is likely the result of a stuck activity record in the Dynamics Activity or Dynamics Dex_Lock table where another user was using the Print 1099 window. I would have all users log out and see if this resolves the error. Otherwise continue with the steps below to clear the record through SQL:
1. Please make sure that you have a restorable back up.
2. Have all users log out of Great Plains.
3. Launch SQL Query Analyzer and run the following statements:
DELETE DYNAMICS..ACTIVITY
DELETE DYNAMICS..SY00800
DELETE DYNAMICS..SY00801
DELETE TEMPDB..DEX_LOCK
DELETE TEMPDB..DEX_SESSION
4. Verify if the issue persists.
Hope this was helpful,
Kelsey Koep