After clicking Pair Next Round in TOM, an error pops up: “Unable to pair any more rounds. The tournament will now end.” TOM shows more rounds remaining. What gives?

This is a known bug in TOM, but luckily it’s an easy one to fix. Dismiss the error dialog, save the tournament, and close TOM. Then, reopen TOM and open the tournament file. You should now be able to pair the next round (likely the first round of top cut Single Elimination).