Last term the Hammers reached the semi-final of the Europa League where they suffered an agonising defeat by Eintracht Frankfurt.
Goalkeeper Areola said: "We did something great for the first time with the club, and now we hope to do even better.
"We are competitors. When you are competing in Europe, you want to win."
The Hammers could hand an instant debut to Germany defender Thilo Kehrer, who completed his £10million switch from Paris St Germain on Wednesday.
Areola, who played with Kehrer at PSG, said: "He's a good player with his feet, he has good experience and he played with some of the greatest players in the world. He's going to bring that experience and quality.
"We went through lots of games together. We had a year and a half together. It's always good to have someone you know on the pitch. You have that confidence."
David Moyes will be serving a one-match UEFA ban after kicking a ball at a ball boy in the defeat in Frankfurt.
Jose Mourinho famously got round a suspension when he was manager of Chelsea in 2005 by hiding in a laundry basket so he could give a team talk.
But first-team coach Billy McKinlay joked that Moyes would not be speaking to his players "unless we get the wheelie bins out".
The Hammers will also be without captain Declan Rice, banned after accusing the referee in Frankfurt of 'corruption', and left-back Aaron Cresswell, who was sent off.
"It was a very, very emotional night," added McKinlay. "We are human. We can make allowances for that a bit.
"We've lost our captain, our vice-captain and our manager. But the manager will still be preparing the team this week and have a big influence.
"It's up to us to deal with that loss but it was such a big game for everybody that circumstances, things happen, just have to deal with it.
"The manager is a big presence about the place so we will have to deal with that.
"The instructions will be the same, we know how he works, we know what he wants, we know what messages to relay to the players so hopefully, it won't have too big an impact."
Opponents Viborg have been dealt a blow after two of their players, Nigerian winger Ibrahim Said and Gambian forward Alassana Jatta, were unable to get visas to enter the country.