When Adrienne Moore switched from an iPhone 4 to a Samsung Galaxy S5 earlier this year, problems with iMessage prohibited her new phone from getting text messages sent to her number. She filed a lawsuit in May, and Reuters reports that US District Judge Lucy Koh has ruled that the suit will move forward.

Apple acknowledged earlier this year that there was a "server-side bug" causing trouble for customers attempting to leave iMessage and deregister their numbers. If your number is still in Apple's system, iMessages sent to you could appear to senders as if they've been delivered even though the recipient hasn't actually gotten them.

Moore claims that the inability to receive messages interfered with her mobile contract, and that Apple violated California's Consumers Legal Remedies Act and Unfair Competition Law. In an earlier motion to dismiss the suit (PDF), Apple said that Moore "did not tell Apple that she was no longer using her iPhone" (in other words, she didn't de-register the iPhone from the iMessage service before getting rid of it), and that Apple never promised that iMessage "would automatically recognize a user's transition to a new device. From that motion:

Apple takes customer satisfaction extremely seriously, but the law does not provide a remedy when, as here, technology simply does not function as Plaintiff subjectively believes it should.

Additionally, Apple claims that Moore has not identified the part of her mobile contract that guarantees delivery of every text message. The company says this invalidates her complaint that Apple interfered with the contract.

Yesterday Apple published a support page to help users deregister their numbers even if they no longer have their old iPhones. Previously, the best ways to leave iMessage were to turn it off before replacing your iPhone or to call Apple's support line.