V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

PEBKAC
       Problem Exists Between Keyboard And Chair (telecommunication,
Usenet, IRC)


The Jargon File (version 4.4.7, 29 Dec 2003):

PEBKAC
 /peb'kak/

    [Abbrev., ?Problem Exists Between Keyboard And Chair?] Used by support
    people, particularly at call centers and help desks. Not used with the
    public. Denotes pilot error as the cause of the crash, especially stupid
    errors that even a luser could figure out. Very derogatory. Usage: ?Did
    you ever figure out why that guy couldn't print?? ?Yeah, he kept cancelling
    the operation before it could finish. PEBKAC?. See also ID10T. Compare 
    pilot error, UBD.


The Free On-line Dictionary of Computing (30 December 2018):

PEBCAK
PBCAK
PBKAC
PEBKAC
PICNIC

    (Or "PEBKAC", "PBCAK", "PBKAC") Tech support
   shorthand for "Problem (Exists) between Chair and Keyboard".

   An alternative is "PICNIC" - "Problem In Chair, Not In
   Computer".

   An acronym commonly used by helpdesk technicians to indicate
   that a problem is due to the user rather than the system.

   See also UBD.

   (2012-08-26)