Electronic communication has upset me — trouble follows (5)

'electronic communication' is the definition.
(email is a kind of electronic communication)
'upset me trouble follows' is the wordplay.
'upset' says the letters should be written in reverse.
'trouble' becomes 'ail' (synonyms).
'follows' means one lot of letters go next to another.
'me' in reverse letter order is 'em'.
'em'+'ail'='EMAIL'
'has' is the link.
(Other definitions for email that I've seen before include "Post" , "Message sent via computer" , "Digital message" , "Spam perhaps" , "Electronic message" .)
'electronic communication' is the definition.
(I've seen this before)
'upset me trouble follows' is the wordplay.
'upset' shows that the letters should be reversed in order.
'trouble' becomes 'ail' (synonyms).
'follows' means one lot of letters go next to another.
'me' written backwards gives 'em'.
'em'+'ail'='E-MAIL'
'has' is the link.
(Other definitions for e-mail that I've seen before include "Online message" , "Transmission of correspondence via internet" , "Online correspondence" , "Electronic message" , "Online post" .)