http://img14.imageshack.us/i/60938815.jpg/
This Image show a Adware Downloader where symantec says: Signature and trustworthy (good)
Here you can see that this C4DLMedia Signature is not Trustworthy
7/41 Detections. Trojan.Win32.C4DLMedia.b / Adware/Gala
This Adware Downloader install -Suspicious.Lop-
http://img2.imageshack.us/i/46215212.jpg/
Delete the bad signatures that lead into a false trustworthy.