I’m about to put you in a difficult position if you haven’t played The Legend of Zelda: Skyward Sword, but you should hear me out.
In order to know what to avoid, you have to tread a bit into spoiler territory--but it’s not that bad.
The glitch occurs during the Song of the Hero quest, if you follow this exact sequence:
- At the beginning of the quest, go to Lanayru Desert to retrieve the song of the Thunder Dragon.
- In the Lanayru Mine, speak with Golo the Goron.
- Complete the Thunder Dragon's event, and receive his song.
- Before heading to the forest or volcano regions, speak with Golo in the mine again.
- At this point, the forest and volcano events will no longer occur, making it impossible to continue.
Tackling the other dragons that are part of the Song of the Hero quest will ensure that the glitch doesn’t occur, however.
Nintendo does not appear to have a clear remedy for this at the moment. I’ve contacted the company about it, but options could include a bonafide patch or issuing fixed saves for users who are already glitched. I'll let you know what I hear.