Frustrated rail passengers took to Twitter more after delays on rush-hour trains into Euston on Thursday morning.
London Northwestern's 07:04 service was delayed leaving Northampton while a fault on the train was fixed.
But the knock-on effect was congestion on the lines into London and delays of up to 20 minutes from Milton Keynes, Leighton Buzzard, Tring, Berkhamsted and Hemel Hempstead.
Passengers at Northampton were also unhappy at station announcements telling them to get off the 07:04 – and then watching it pull out ahead of the 07:15 they were told to travel on!
One distgruntled traveller tweeted: "What is going on at Northampton this morning?
"Guards told us the 07:15 would be going direct to Euston so we all got off. Then the 07:04 goes and we're still on a train that's not left and that’s not going direct."
A spokesman for train operator London Northwestern said: "We apologise to any passengers affected by the hold ups.
"It looks like the 07:04 was delayed due to a fault. This was resolved within ten minutes but this may not have been known at the time the information was given.
"Later services were then affected by that service causing congestion on the line.
"Any passengers whose journey is delayed by more than 15 minutes are entitled to compensation under our Delay Repay scheme."