error messages - what to display in text?

Translating unsuccessful scenarios to reasonable text messages can be very tough from a developers perspective. Here is one example. I tried to call my friend on skype, whom I talk at least twice or thrice in a week. He sometimes logs in invisible mode...

It seems he isn't online, and here is the error message i get..



Comments on the text:

(a) "User not found" ? and in the next line i have the name of my friend displayed..
(b) "has not been online recently..." ? i spoke to him couple of days ago.. how recent is recent

Wouldn't it be easier to just say either:
(a) "Cannot complete the call. User is not online." or
(b) "Cannot complete the call. Santosh is not online."