Huge numbers of BT Broadband customers across the UK had their services cut off after a "power failure" at a major exchange in Birmingham this afternoon.
The company said those affected numbered into the hundreds of thousands - about 5% of its total customers - with many business customers losing considerable revenue as a result. But what rights do those affected have in this situation?
The BT shut down did not last long. The first reports of problems began emerging at about 1pm.
And by earlier this evening, BT issued a statement saying that the service had been fully restored, and advising customers still encountering connection problems to "turn their hub or modem off and on again".
In fact, many consumer package customers were able to get back online by 3pm, although business customers had to endure longer delays.
In a statement, the company said: "We can confirm that, as a result of a power failure at one of our major exchanges, some customers may have experienced loss of broadband service for a brief period this afternoon.
"All services have now been restored, with the majority of BT's consumer broadband customers' service being restored within just one hour.
A break in connection is frustrating no matter how long it lasts for, though. And for business customers, many of whom had to wait several hours to get back online, being unable to connect with potential clients is also an expensive business.
What are my consumer rights?
Generally speaking, your broadband provider has a duty to provide you with a working internet connection. However, should this connection fail, it also has a certain amount of leeway when it comes to fixing it.
You can, for example, request a reduction to your bill according to the length of time that your connection is down. But this only really comes into play if you are without the internet for much longer than a couple of hours.
If, for instance, your broadband does not work for four weeks after activation, then you have the right to cancel your contract under the "termination clause".
What about business broadband customers?
Though business broadband deals are usually more expensive than those for regular home use, they are generally considered to be a worthwhile investment due to the priority technical support offered to business customers.
That said, BT only guarantees to repair a BT Business Broadband Network and BT Business Broadband Network Premium Service Failure in line with the timescales set out in the Service Schedule, which in turn states simply that "BT will respond to reported faults as soon as it reasonably can".
Should the company fail to do this, you can claim a one off Service Level Credit of £25. But that is of little comfort to those affected by today's "power failure" - especially as they are unlikely to qualify for a payment even for this amount given the limited time they were without internet access.
Can I take my complaint further?
If you want to take things further, you can contact independent adjudicators Cisas or Ombudsman Services: Communications for help. Both provide a free service to help solve disputes between members of the public and broadband suppliers.
However, you must give your provider the chance to respond to your complaint first. To improve your chances of success, it is also a good idea to keep a record of how many calls you have had to make, and how long they lasted, as well as who you spoke to and what they said.