PEBCAK

from The Free On-line Dictionary of Computing (8 July 2008)

PEBCAK
PEBKAC

   <humour> (Or "PEBKAC") Tech support shorthand for "Problem
   Exists between Chair and Keyboard".

   See also {UBD}.

   (1998-08-27)

from V.E.R.A. -- Virtual Entity of Relevant Acronyms (June 2006)

PEBCAK
       Problem Exists Between Chair And Keyboard (slang)