Passengers flying into the country were made to wait for up to four hours as staff battled to process long, slow-moving queues of weary travellers. While some airports reported the 24-hour glitch having little impact on their operations, others said non-EU passengers had to endure tedious waits as tempers boiled - with little communication from the Government about when the congestion might ease.
It prompted immigration and security minister James Brokenshire to visit one of the affected airports - Heathrow - yesterday morning.
He said: "Our engineers have been working through the night to fix the temporary IT problems and all ports are now functioning normally. We apologise for the delays that some passengers experienced at passport controls yesterday, but security must remain our priority at all times.
"I visited Heathrow early this morning and have asked technical staff to continue to look into the incident to ensure lessons are learnt."
One Heathrow passenger, who arrived on a delayed flight from Vienna described the scene in the arrivals hall as "chaos". The 32-year-old project manager, from south west London, who asked not to be named, said: "Nobody seemed to know what was going on, and there was nothing forthcoming from officials. As you can imagine, there were people there who had come off 18-hour flights, very tired, and obviously it was pretty unpleasant."