Antivirus Alert - TROJAN -BBManager

I was going to install the last version of the BBM and my antivirus, Avira, shows an alert
file: Qt5webkit.dll
Tojan: crypt.zpack.gen2
so i stopped installation
what do i do?
some info?
thanks

VERSION 1,65

Allow your AV program to trust the BBM install.

If you downloaded the software directly from our forum, it’s a false positive. Manually allow to it to install.

hello
thanks for the (very brief i think) answers
i checked the file with avira online file checking and they say: ‘Clean’
seems ok then