After the correct move Qg8, the next move i played 2. Qh8 and this message shows:
2.Qh8 lets Black get back to hem in the white king, and to protect his own king, with 2...Qf7
This is wrong because after Qf7 follows Qe5+ Ka8 Qa5+ Qb8 Qa7#. The correct response should be *2.Qh8 allows 2... Qa8 and repetition of the position follows*
Silman's Lessons in Strategy (1) Author(s): IM Jeremy Silman
After completing i went over some other moves and when i tried 1... Rb8 to see what the message said:
If your move doesn't keep the White Knight out of h4, give up on it and look for something better.
Technically Rb8 does keep the white knight out of h4 because of the tactical threat on e4. After 2. Nh4 Nxe4 follows and the knight on h4 is attacked by the black queen. 3. Bxe4 now doesn't attack the hanging bishop on b7 because the rook protects it. This is a typical tactic but ok i guess the move isn't positionally sound because nh7 is better and straight-forward but an explanation as to why Rb8 isn't necessary would have been nice.
While i was completing:
D. Joseph 1922 Endgame Study
i found a mistake...
After the correct move Qg8, the next move i played 2. Qh8 and this message shows:
2.Qh8 lets Black get back to hem in the white king, and to protect his own king, with 2...Qf7
This is wrong because after Qf7 follows Qe5+ Ka8 Qa5+ Qb8 Qa7#. The correct response should be *2.Qh8 allows 2... Qa8 and repetition of the position follows*