The London Stock Exchange website has been inaccessible from Google this morning, after it was reported as a virus attack page.

The news comes at the end of a tough fortnight for the exchange, as market data vendors display inaccurate stock prices following the rollout of its new Millennium Exchange trading system. The exchange also suffered a major, unexplained outage for four hours on Friday. An emergency meeting with data vendors has been scheduled for Tuesday.

The site continues to function for those who have bookmarked it, but access was blocked from the search engine after links appeared to a compromised site. The website provides up-to-date information including stock prices, company news and technical specifications for trading firms.

It is understood that the problem originated at an advertising company with promotions on the site. If users clicked through a link on an advertisement, then clicked a second link, they reached a compromised site.

The LSE has removed the advertisements from that provider, and it is expected that Google will shortly reinstate direct links to the exchange website from search.

Different browsers are affected in different ways. As of 10.30 am today (Monday), access does not work from the Mozilla Firefox browser, but it does work from Microsoft Internet Explorer.

An exchange spokesperson said the site itself was now “working fine”, and that access was available – at least on some browsers – by going direct to www.londonstockexchange.com.

Meanwhile, it is understood that trading has resumed successfully today on the exchange, following Friday’s high-profile data problems.

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