Hi Sagar,
You have to disable it using the Management Server, since it's being centrally managed.
The location in SmartEndpoint is under "Policy - Sandblast Agent Threat Extraction and Emulation - Protect web downloads with...", where you can choose if you want Threat Emulation, Threat Emulation and Threat Extraction, or "Do not use web download protection". Another component of the browser plug-in is zero-phishing. You also can find it in the same section under "Zero phishing settings" where you can set the phishing protection to "Off".
This have to be done with a SmartConsole R77.30.03, since in R77.30 these options don't exist and this is probably the issue 🙂 You can download it from here.
Hope this helps!
Note: you may also give a try to the browser plug-in. It's really nice and a good choice to have a real prevention from zero-day threats.