Blocking of an .exe download on firefox wrapped with launch4j

[nfouka]

I use launch4j to wrap a java executable with an embedded jre, my goal is to put this executable on an apache2 server to make it available to my clients to download and install.
The problem: when I try to download it from firefox my antivirus blocks the download and I have no log message to identify the origin of the blocking. the download works on google chrome and IE.

Do you have an idea ?

[camhart]

Signing the exe could help.