Update: It takes more than a nasty system outage to hold the Footsie back. Today, anyway.

The UK’s blue-chip index has just closed for the day, with solid gains, as traders put this morning’s 100-minute outage behind them.

The FTSE 100 gained exactly 50 points, or 0.7%, to finish at 7,117 - a small but welcome improvement on Thursday’s six-month low.

Other European markets clambered back off the mat too, with Germany’s DAX up around 1.3%

Connor Campbell of SpreadEx says the FTSE came “fashionable late” to the party.

Better late than never! The FTSE finally was able to join the market relief rally on Friday after being held at the gate this morning.

Working on the hopeful assumption that central banks are going to step in and try and force the global economy into a U-turn away from a recession, the markets were fairly uniform in their gains.

There should be red faces at the London stock exchange today, says Fiona Cincotta of City Index.

She writes:

After a rare delay, trading on the FTSE finally kicked off almost two hours later than usual on Friday. The opening auction started at 09:20 with stocks opening for trading at 09:40, well after the standard 08:00am start in what was the longest glitch since 2011. This is the second glitch in two years, the last one was a year ago saw the FTSE open 1 hour late.

There is no hiding from this one, the two-hour delay to open is an embarrassment for LSE and raises plenty of questions over the group’s technology. The timing is pretty horrendous for LSE, just weeks after it sealed a deal to buy Refintiv, in its quest to become a global markets and information powerhouse. LSE’s reputation as one of the most reliable stock exchanges in Europe is starting to be questioned.

Unless there’s a strong late rally, Wall Stree will post its third weekly decline in a row.

Stocks are down around 1.7% this week, mainly due to Wednesday’s tumble (which wiped 800 points off the Dow).

No-one is immune to the kind of systems failures that hit the London Stock Exchange this morning, of course.

Back in 2015, Bloomberg’s systems crashed for several hours - leaving traders unable to operate, and even forcing the UK government to delay a debt auction.

The disruption was blamed on an “internal network error”.... but there was a rumour, alas never confirmed, that an IT worker had accidentally spilt a can of coke on a server.

The US stock market is expected to rally when it opens in an hour’s time (unless London’s tech gremlins scamper across the Atlantic and wreck more havoc).

The Dow Jones industrial average is up 230 points in the futures market - which would recover a chunk of Wednesday’s 800-point tumble.

Traders are citing hopes of a US-China trade war breakthrough, after Donald Trump said he hopes to speak with Xi Jinping soon.

But let’s not get carried away; as things stand, America will impose fresh tariffs on Chinese consumer goods next month, meaning Beijing will retaliate.

Money is still pouring into the world’s government bond markets today, as asset managers look for a place of safety.

Prices are hitting new highs, dragging yields (the rate of return on the debt) to fresh lows.

Germany’s 10-year bund yield, for example, just hit minus 0.72% for the first time ever -- meaning investors are prepared to lose money to lend to Berlin for a decade.

They’ll be calculating that the European Central Bank’s forthcoming stimulus package will drive bond yields even lower, as the ECB will create new money to buy bonds with.

Sweden is also benefitting -- its 20-year bond yield has just tumbled below 0%. That means the entire Swedish bond yield curve is negative (longer-dated debt is yielding less than short-dated bonds).

That shows investors are pessimistic about growth prospects, having noticed that Sweden’s economy contracted in the last quarter.

Here’s our news story on the gremlins taking control of the London stock market.

The LSE won’t say exactly what went wrong this morning, apart that the problem centred on its software.

Here’s the official statement:

London Stock Exchange experienced a technical software issue this morning that affected trading in certain securities, including FTSE 100 and FTSE 250 stocks.

Following resolution of the issue regular trading in all securities commenced at 09.40.

That issue scuppered the usual pre-open auction (which helps to set prices before trading gets underway at 8am).

AJ Bell investment director Russ Mould says today’s problems have livened up an otherwise dull morning:

Investors would have been yearning for a quiet Friday after a week of turmoil for the markets driven by recession fears.

“And it looked like just such a peaceful interlude was on the cards until technical issues at the London Stock Exchange delayed the start of trading in FTSE 350 stocks, delaying an expected rebound for the index.”

Today’s stock market glitch hasn’t affected the pound, which has just jumped to its highest level in eight days.

Sterling has gained 0.5% against the US dollar to $1.2141, as the campaign to prevent a no-deal Brexit in October gathers pace.

Earlier today the leader of the Liberal Democrats, Jo Swinson, insisted that an emergency government could be installed to prevent Britain crashing out of the EU, and that Conservative grandee Ken Clarke and senior Labour MP Harriet Harman – the father and mother of the house – are both willing to lead it.

The London Stock Exchange has just revealed that some buy and sell orders that should have expired this morning are still lurking on its trading platform.

That may explain why trading was delayed for so long.

The LSE says:

GTD orders expected to expire this morning have remained in the system.

These orders cannot be traded against and are still being advertised via Market Data. This has caused crossed order books. This is being investigated and an update will be provided at 10:30.

What, I hear some readers cry, is a GTD order?

It stands for ‘good until date’ -- an instruction to one’s broker to maintain a buy or sell order until a specific time. Then it would expire, unless it had already been executed.

Failing to cancel a GTD order as instructed would cause problem -- asset managers might find they’ve bought or sold something they didn’t mean to.....

The London stock market seems to be trading normally now, after being stricken for more than an hour and a half.

Every sector is higher, with telecoms, financial stocks and healthcare leading the way.

But even so, investors didn’t need the drama, following the wild swings in asset prices we saw this week.

The BBC’s Victoria Fritz points out that nerves were already frazzled by recession fears.

This is more like it!

The market has “transitioned to regular trading”, says the LSE’s status page, as it picks up the pieces following this morning’s debacle.

The Stock Exchange is creaking into life!

The FTSE 250 index (which contains mid-sized companies) just rose by 0.01% -- a teensy change, which means something has started trading.

Trading is now expected to begin at 9.40am - 100 minutes late.

Reuters points out that today’s outage is the longest since February 2011, when the market was shuttered until lunchtime.

Today’s technical problems are the third to strike the UK this month alone.

Last Wednesday, thousands of passengers at British Airways were stranded after its systems collapsed. Two days later, major power cuts struck the country after the National Grid’s network failed.

There’s no suggestion that the three are linked (the power blackout is being blamed on a technical fault at the world’s largest offshore wind farm, Hornsea One).

But still, this hat-trick of problems doesn’t reflect well on Britain’s infrastructure.

Neil Wilson, analyst at Markets.com, agrees that the outage is frustrating:

Still waiting...the FTSE cash equity market has failed to open and remains closed for the time being. The FTSE 350 is closed but AIM trading is still ok.

These things happen – the last delayed start to trading was only a year ago. Technical glitches are inevitable, frustrating as it is for everyone.

Wilson also points out that the Footsie SHOULD be rallying, having slumped to a six-month low of 7067 points last night.

FTSE futures are trading – and our fair value estimate suggests the cash market will open up strongly around 7115.

Frustration is mounting in the City.

London’s stock market has now been frozen for an hour -- leaving traders unable to buy and sell shares in the 350 biggest companies listed on the FTSE.

And they’ve still not said what’s gone wrong, or when the problem will be fixed.

The London Stock Exchange still hasn’t got its systems working.

It has just told traders that the next update will come at 9.15am BST.

The technical outage in London is preventing UK stock traders from joining in today’s market rally.

As you can see, every other major European stock index is higher this morning - as shares recover some of this week’s heavy losses.

Craig Erlam of trading firm OANDA warns that the markets could soon turn volatile again - so the LSE needs to fix its problems, fast:

Investors are more relaxed this morning than they’ve been for the rest of the week but it would be naive to expect it to continue. There’s been plenty of whipsaw action this week so to assume today will remain calm may be asking a bit much.

The FTSE failed to open on time on Friday due to a potential trading service issue. Unfortunately, I don’t think we can blame Brexit for this one but maybe I’ll be proven wrong.

Stock market traders are venting their frustration at the London Stock Market’s IT systems, by posting memes on social media.

Nothing is moving on the FTSE 100 this morning, as the LSE scrambles to work out what’s gone wrong.

This is the second time in 14 months that London’s stock exchange has suffered problems.

In June 2018, the opening of trading was delayed by an hour - a serious embarrassment to the City. That was the first outage in seven years.

The LSE says it is “currently investigating a potential trading services issue”, which is stopping investors buying and selling shares this morning.

The prospect of a new ECB bazooka is acting like catnip to European traders.

Germany’s DAX index has jumped 0.4% in early trading, while Paris’s CAC and Milan’s FTSE MIB are both 0.3% higher.

Spain’s IBEX is also in the green, as Olli Rehn’s promise of a “strong” stimulus programme reassures the markets.