To request computer assistance is to invite trouble (3,3,2)
I believe the answer is:
ask for it
'to invite trouble' is the definition.
(I've seen this in another clue)
'to request computer assistance' is the wordplay.
'to request' becomes 'askfor' ('ask for' can be a synonym of 'request').
'computer assistance' becomes 'IT' (IT support).
'askfor'+'it'='ASK FOR IT'
'is' is the link.
(Other definitions for ask for it that I've seen before include "invite punishment" , "court problems?" , "Informally, invite or deserve trouble" , "Invite trouble, behave provocatively" , "Court trouble" .)