LONDON: The London Stock Exchange Group Plc resumed trading an hour late after its opening auction was delayed, the first major outage of its kind in seven years.

Regular trading on LSE commenced at 09:00 U.K. time as the opening auction was postponed due to a technical issue that has been resolved, the exchange said on Thursday. 

The 217-year-old bourse operates one of Europe’s largest cash equity markets. LSE’s main equity market and Alternative Investment Market were among those affected.

Some traders were left frustrated by the delayed open and said market operators should have better back-up plans in place.

“There should be some other mechanism that allows it to be counteracted,” said Atif Latif, director of trading at Guardian Stockbrokers in London. 

“On a heavy dividend day and with the recent price volatility, we had to gauge prices based on the European market and index futures.”

“It does highlight a lack of contingency plans when these issues arise, given the heavy investment in IT and infrastructure,” he said. 

LSE in recent months has also experienced issues with its regulatory news announcements. It has been without a permanent chief executive officer since Xavier Rolet departed in November, although the exchange has David Warren running the LSE in the interim. 

The new chief, former Goldman Sachs Group Inc. executive David Schwimmer is due to start in August.

The London bourse’s last major outage was in 2011, after it moved to a new platform called MillenniumIT. Sri Lanka based Millennium Information Technologies is the LSE unit which develops high performance trading systems and financial markets software.

Last month, LSE said it was setting up a new business centre in Bucharest employing 200 people to deliver technology and data services.

The benchmark index FTSE 100 was little changed as of 10:34 a.m. in London trading. - Bloomberg