Random ERR_Empty_Response message on different sites and browsers

Question

I am having a weird issue that seem to start after upgrading to the latest firmware (SFOS 10.0.4 MR-4). Some sites, it seems to happen randomly, will not load and give the message ERR_Empty_Response. It seems to happen after trying to login to the site. Sometimes, if I clear out the cookies, it will work but then a few minutes later it will do it again. I have a site currently that does it all the time, but it works outside of the network (At Home). If I add an exception to the firewall for the for the domain, it will fix it sometimes. When it pops up, if I hit the information button next to the url, the browser says your connection isn't secure. Then another click on that says This site does not have a certificate. It's very strange and like I said it is random. It has happened on Dell.com. microsoft's live.com, DHL.com, and Regions.com to name a few. The main page seems to load but after any authentication, you get the err_empty_response. I thought it might be a browser issues, but it works when outside of the network. It also started happening right after the firmware upgrade which is why believe it is something on the XG. I contacted support and they were no help. Just the routine of trying things and they just closed my ticket out without resolution.

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emmosophos · Answer

Hello Tom, 
 Thank you for contacting the Sophos Community. 
 Would it be possible for you to share your Case ID. 
 As per the issue, try the following: 
 1. Connect to the device console via SSH or directly with a keyboard/monitor or serial cable. 2. Login 3. On the main menu, select (4) Device Console 4. At the prompt, to increase the timeout to 3 minutes from the default of 60 seconds, enter the following: 
 console>set http_proxy response_timeout 180 
 Might be worth also checking your DNS settings in the XG if you aren&rsquo;t using a Public DNS resolver try adding one. 
 Regards,