delete win32:Trojan-gen in a mac computer

Avast Mac Security
1

Hello,
I get the message ( see picture) of infection blocked. But everyday this message is hoping up. Any idea to eliminate the Trojan. The file infected is the file mail in the mail app folder (see picture).
I uses mac with Yosemite 10.10.1
Avast 10.4 (434119)
VPS: 15012700
Thank you

/Users/Casarbol/Desktop/Captura de pantalla 2015-01-27 a las 12.00.30.png
/Users/Casarbol/Desktop/Captura de pantalla 2015-01-27 a las 12.03.17.png

2

Hello,
attach the picture(s) to the post, please. You can use http://support.avast.com/ → Avast Virus Lab to sent the files for analysis.

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