Fail to pick up email, even with son having try! (7)
I believe the answer is:
mishear
'fail to pick up' is the definition.
(I've seen this before)
'email even with son having try' is the wordplay.
'even' means one should take alternating letters (even-numbered letters are used).
'with' is a charade indicator (letters next to each other).
'son' becomes 's' (genealogical abbreviation for son).
'having' means one lot of letters go next to another.
'try' becomes 'hear' (as in to try someone in court or hear their case).
The alternate letters of 'email' are 'mi'.
'mi'+'s'+'hear'='MISHEAR'
(Other definitions for mishear that I've seen before include "Incorrectly pick up" , "Pick up wrong" , "Wrongly catch" , "Fail to pick up" , "Sense (words) wrongly" .)