"I do not know this information."
Translation:Εγώ δεν ξέρω αυτή την πληροφορία.
No, πληροφορία is a countable noun in modern Greek. Its plural form is πληροφορίες. You can think of it as the equivalent of piece of information.
I hope this helps. :-)
I thought in Greek information was normally used in the plural - at any rate that's my experience from airports etc - so shouldn't πληροφορίες be allowed?
Πληροφορίες means pieces of information, but it is also a fixed expression for information booths. That's why you've seen it at airports. ;-)
Yes. It seems like one of those sentences where the rule wasn't taken into consideration. (sigh). However, the alternative with αυτήν should be accepted. ^.^