In LR 2015.7 the "X" key is assigned to two functions in the library module:
Reject photo (Foto/Ange flagga/Avvisad)
Show info (Visa/Format för stödrastervisning/Visa information)
Now, this is a total screw-up since the X (=Reject) function is SUPERIMPORTANT to every workflow. Unfortunately, when you press X the other function has priority. Luckily, Shift-X still works to reject a photo and jump to next.
My guess is that this is only in the Swedish version (any maybe some other obscure languages) or you'd have a huge mob right outside 345 Park Avenue in San Jose.
Come on Adobe! Just have an intern check the keyboard shortcuts before you release! Or even better, give us shortcut customization. Arrrgh... 😞
This appears to be fixed in CC 2015.9 / 6.9. The release notes say only that it was fixed for French, but examining the TranslatedStrings.txt file, it looks like it was fixed for Swedish too. Please post here if 2015.9 / 6.9 doesn't fix the issue.