Scotland's Kirsty Gilmour suffered a shock first-round exit on the opening day of the World Championships in Copenhagen.The Commonwealth Games silver medallist lost 21-15 21-15 to Germany's Karin Schnaase at the Ballerup Super Arena.
England's Chris Langridge and Heather Olver - who also won silver in Glasgow - overcame Canadians Toby Ng and Alex Bruce 21-6 21-13 in the mixed doubles.
Compatriot Sarah Walker beat Malaysia's Sannatasah Saniru 21-18 19-21 21-12.
She will play Korean fifth seed Sung Ji Hyun in the second round on Tuesday, while Langridge and Olver face Danny Chrisnanta and Yu Yan Vanessa Neo, the ninth seeds from Singapore.
England's Fontaine Chapman, making her World Championships debut, lost 28-26 21-17 to Commonwealth champion Michelle Li, from Canada.
Scot Imogen Bankier, bronze medallist in the mixed doubles at Glasgow 2014, and Bulgarian Petya Nedelcheva were beaten 21-19 9-21 21-12 by Indonesia's Suci Rizky Andini and Tiara Rosalia Nuraidah in the women's doubles.
Kate Robertshaw's withdrawal through injury prevented her and Olver from facing India's Jwala Gutta and Ashwini Ponnappa, who claimed a walkover win.
English husband and wife fourth seeds Chris and Gabby Adcock, who beat Langridge and Olver to mixed doubles gold at Glasgow 2014, face Malaysia's Aik Quan Tan and Pei Jing Lai on Tuesday after receiving a bye in the first round.
England's Rajiv Ouseph plays 16th seed Wei Feng Chong in the men's singles first round.