You are welcome.

I had no problems until i upgraded to the new 2.6.7 and instantly i cant create frontend or backend items as i get blank page with popup of "calendar.set up: Nothing found...."

I have not touched the backend creation form nor hidden calendar. Its been working fine before the upgrade. I added to this post cause it touched on same error message. my forum post about this is getk2.org/community/New-to-K2-Ask-here-first/179521-Upgrade-issue-267-Calendarsetup-Nothing