false positive Win32:Evo-gen [Susp] ?

So I have a rar SFX archive that I use AutoIT to change the icon (because it’s easy for me to just run an autoIT program to change the icon), however when I try downloading the program off my website, Avast blocks it and says it is malware, Win32: Evo-gen [Susp].

I KNOW 100% certain that it is NOT malware, since I have created everything along the way myself. And I’m pretty sure the autoIT program I use to change the icon is legitimate. If I upload it to a site that scans using all antiviruses such as virustotal, I get 0 detections (even from Avast). I don’t want to release this sfx archive to the users of my website if avast says it is suspicious since that could hurt my website’s reputation.

The detection is coming from the file system shield. If I scan the file directly (with avast or mbam), or upload it to a site that scans using lots of AV’s, no detections are found.

How do I fix this?

You can report a possible FP here: http://www.avast.com/contact-form.php