Delayed starting downloads

Question

Since I use a XG Firewall, my Downloads are starting with a delay of 10 up to 15 min. 
 After ~50% the download fails/interrupts. 
 I use a Sophos XG home with a 4 core Intel i5 and 6 GB of Ram. 
 I also tried Web caching and to reduce max. file scan size, but nothing changed after that. 
 Thank you for your help!

FormerMember · Accepted Answer

Good evening, 
 
 I switched now to realtime-scanning in Web>Protection>Malware-Scan mode. 
 Now my problem with delayes and interrupting downloads are fixed ,but when I now try to download EICAR-Testfile, it won't be downloaded, but I only see a white page and NO "Virus found" message/alert. 
 How can I fix this Problem?

sachingurung · Answer

Scanning 1535 MB file is huge, it will definitely take a lot of time which can cause delays during the download. Please change this value to 30 MB. 
 Alongside, define single scan in the Scan Engine selection and configure the Malware Scan Mode as Real Time. This scanning mode scans files in Real Time while they pass through the UTM. Whereas, batch scanning mode caches the files as they come in and then examines them for viruses once they are fully cached. Hence, in the case of bulky files, there is a delay in the scanning because XG waits for the whole file to be downloaded and then starts scanning. 
 Hope that helps.