The cards could be applied for from today but as there are only 10,000 now available, they are being issued on a first-come, first-serve basis, the Rail Delivery Group (RDG) said.
Although 4.5 million people could benefit, just 10,000 railcards are being offered on a first come, first served basis - meaning only about one in 500 people in this age range will have one.
It is thought that demand for the tickets is particularly high because only 10,000 have initially been made available as part of a limited trial of the scheme.
But dozens of passengers took to social media on Tuesday morning to express their frustration at being unable to use the website selling the cards.
A nationwide trial of the so-called "millennial railcard" descended into chaos this morning, with the mad scramble to secure the discount cards causing the website to crash. However, only 10,000 went on sale and cash-strapped young people complained they were more hard to get hold of than Glastonbury tickets. "Sort out your website to make it fair!"
The 26-30 railcard was announced in late 2017, and allows users to save a third off most fares, although no discount can be used on season tickets, and the cost of some peak time travel will not be reduced.
Tom Drury, from London, wrote: "The launch of the new railcard is a shambles". "We're really sorry this is happing and have our whole team on it". There will be a £12 minimum on tickets between 4.30am and 10am, excluding weekends and public holidays.
Although the decision to make travel cheaper for greater numbers of young people has been widely welcomed, some have said it does not go far enough to solve the transport and economic problems affecting the UK.
Currently, people aged 16-25 can buy a rail card to get a third off their fares, as well as couples in a Two Together scheme, or families in a group card.
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One of the wounded men was living and working on the property but had been asked to leave, Lusczynski said. Bliss Enterprises is a family owned construction company that has been building barns since 1982.
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After $1.14 actual EPS reported by Mastercard Incorporated for the previous quarter, Wall Street now forecasts 9.65% EPS growth. General Electric accounts for 0.9% of Twin Capital Management Inc.'s portfolio, making the stock its 24th largest position.
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However, for the ones who have never flashed an Android device, it is advisable to wait for the official OTA update from Xiaomi. If you haven't installed the MIUI 9 Global ROM, you can follow the below procedure to get the software on your Xiaomi phone.