United were beaten 2-1 on Sunday, with VAR awarding the Hammers an injury-time penalty which Jarrod Bowen converted for the winner.
Ten Hag said, “Last year was not different, but in the end we turned it around and we are so determined it will be the same this year.
“If we can continue how we are playing now against Brentford, Fenerbache and today… we will achieve this.”
United now have four consecutive games at home.
And Ten Hag continued: “I trust in my team, it is not about correcting them, it is about trusting them for the next game. I believe my players are capable of this.
“I trust them and encourage them to keep going. They have been doing this for long periods over this game and other games.
“Eventually we will find the net and we will win more games.”