| Luxembourg to Oslo via Amsterdam. Early morning flight from Luxembourg to Oslo via Amsterdam. Shortly before boarding they announce there is a technical problem. About 45 minutes later I call KLM for advice whether to rebook immediately for fear of missing the connection in Amsterdam. Person on the other end is of no help and barely understands my question. About 90 minutes after we were supposed to board, flight is cancelled and we are advised to go to counters for rebooking. While waiting in line I discover an e-mail from KLM saying they've rebooked us to an evening flight, which means delay in arrival of about 12 hours, midnight instead of noon. At the counter we are informed there are no available earlier flights and we get zero information about EU directive for compensation in case of delay, just a useless peace of paper saying they're sorry and how I can contact customer service on Twitter. We get vouchers for 10 EUR of airport food and that's it. On the evening flight there are problems as the airport system says the flight is closed and we cannot go to security, takes about 20 minutes to clear that up. Flight to Amsterdam goes smoothly and we arrive practically on the gate for the connection. Flight Amsterdam to Oslo is delayed about 15 minutes. On the way back, Oslo-Amsterdam goes well. Amsterdam to Luxembourg, they put us in the plane and announce there is a delay due to strike of Belgian air control, will take about 20 minutes, ends up taking 35, and then they discover a technical problem and call maintenance. Another good 20 minutes until they reset something, and we are good to go. Which means another 10-15 minutes plus long taxi. During lift-off, drops of water fall on my husband sitting next to the window, most likely condensate due to poor isolation on the cabin roof. Also once during the flight. First time flying KLM, two delays in a week, and one of those significant. We planned a day and a half in Oslo and this delay significantly influenced our schedule, not to mention we were horribly tired after waking up at 4 to catch the first flight and then waiting an entire day for the next one. The only reason they are getting 4/10 is that the customer service answered my e-mail quickly and said we were eligible for compensation according to the EU directive. However, had I not known my rights, KLM certainly would not have informed me of them. Would not recommend and will not fly again.