I find that big file (say 300M bytes) download is corrupted when the "Enable HTTP checking" checkbox under HTTP filter is ticked. If I untick it, the file can be correctly downloaded. Tried to tick it again and re-download the same file, corrupt again. Also tested with different big files from different web sites. Same problem. I'm using ESET NOD32 Antivirus 3.0.669.0 in Windows XP.