Shares of N Brown, which also said it would cut its dividend by 50 percent to 2.83 pence to a more "sustainable level", fell 17 percent to a more than 13-year low in early trade.
The company, which posted a 5 percent drop in half-year adjusted pretax profit on Thursday, said it plans to spend more on promotions as it revamps to an online business model.
Over the last few years, N Brown has been trying to move most of its sales online as intense high street competition has forced many retailers to close physical stores. It closed its last 20 stores in August.
The company's chief executive officer, Angela Spindler, stepped down last month.
"Whereas much progress has been made transforming the business into an online retailer, we have not yet achieved the growth in product or international that we would have hoped for," Chairman Matt Davies said in a statement.
N Brown said that its overall revenue rose 1 percent, but added that product revenue fell more than 3 percent. Margins declined 60 basis points for the six months ended Sept. 1.
The company, which is moving away from catalogue's to web sales, said online sales rose 3.8 percent and accounted for 77 percent of product revenue.
(Reporting by Sangameswaran S and Karina Dsouza in Bengaluru; Editing by Bernard Orr)