When you want ot download anything it basicly scans the whole download(i think)
You're spot on there. The data scanning plugins require a whole file before they are able to scan the file and make a decision on whether the file is safe to be passed on to the client. So WinGate downloads the file in it's entirety and scans it before any of the file is passed on. To the client, this will seem like a long delay before the download starts (stalled at 0%) and then a very rapid (practically instant) download from 0% to 100%. The time it takes to finish the downloads is actually no longer than if the download was performed directly, but this method of holding back the file does in nature break streaming of any sort.
However, all is not lost. There is a feature in WinGate called drip-feeding that solves this problem. Drip-feeding passes the first 75% of the file to the client as it is downloaded from the internet, but holds the last 25% back to give the data scanning plugins a chance to scan the entire file before completing the download. It still has the option to halt the download making the file on the client incomplete and (hopefully) corrupted as a result.
As the first 75% of the file is passed on as it is downloaded from the internet, this allows streaming to occur normally. You may notice a short pause at 75% of the file download while WinGate finishes getting the file and scanning it.
To enable drip-feeding:
1. Open GateKeeper and navigate to Services -> WWW Proxy Server -> Plugins
2. Enable "Drip-feed data to client if file bigger than X kB" (where X is customiseable)
3. Click OK to finalise the change.