The Mighty River Power share offer website was this afternoon buckling under the weight of hits as would be investors flocked to secure additional share entitlements.

The website, where individual New Zealand investors can pre-register their interest in buying shares in the state owned power generator later this year, went live this morning but by early afternoon many users were experiencing difficulty getting onto the site.

Staff at the share offer's call centre advised trying again "in a few hours".

Some users that were able to access the site reported difficulties in completing the pre-registration.


Some investors on the forum reported being stymied repeatedly as they tried to confirm their pre-registration.

"If this is any indication of how the whole thing will be run then most Kiwis will give up in despair or think they've registered and end up missing out," said one.

"I wonder if the website was designed by Talent2," said another.

Others said they'd experienced no problems.

"I have registered the whole family and all the members of the nearest cat colony - hopefully Gareth Morgan doesn't kill them off before the IPO."

Prime Minister John Key yesterday said individual New Zealand investors will be "favoured at every turn" of the sales process.

Finance Minister Bill English and State Owned Enterprises Minister Tony Ryall added another sweetener this morning in the form of an extra 25 per cent more shares than those who don't pre-register if demand exceeds supply.

The development comes as the government ramps up a campaign to promote the $1.8 billion selldown of the state-owned power company.

Read the Government's pre-registration Q & A here.

Pre-registration for the retail component of the sale is only open to New Zealanders and doesn't include institutions, they said.

No details were given of the wholesale part of the sale, where shares are sold to institutional investors, or on how the price will be set. The price of share sales with a retail and wholesale component are typically set via a bookbuild with institutions.-

See an infographic showing the process released by the Government this morning.

The next three weeks will see the government mount a $1.1 million mass market television, newspaper and internet campaign to entice kiwis to invest in the 49 per cent of MightyRiverPower going on offer.

The government said yesterday it is aiming to ensure 85 per cent to 90 per cent of the shares on offer are bought by New Zealand investors.

The pre-registration website is here.

- with BusinessDesk