Certificate Warning with https set to "URL filtering only"

Question

Hi guys,

we installed a new system in a VM at a customer.

Enbaled Webfilter set to transparent mode and set HTTPS scan settings to "URL filtering only". This should normally not produce any certificate warnings... but IT DOES.
Any client who accesses a secure site gets a warning shot in the browser.
I disabled, enabled webfilter, restared the GW.. always same strange bahviour...

The only way at the moment is to enable "Do not proxy HTTPS traffic in transparent mode" but thats not what we want...

...any ideas??

Cheers, kdessis

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JoshuaKirkwood · Answer

I was having the exact same problem outlined by Kdessis and found that my UTM wasn't wasn't resolving any external addresses. I have my interfaces configured in bridge mode and had the IPV4 default gateway address set incorrectly. After changing this I was no longer having these issues as the URLs were able to resolve correctly. 
 
As outlined by others below the certificate error was showing up as the UTM network unreachable page was being displayed with SSL. 
 
Just thought I would add incase anyone in the future comes across the same issue as KDessis as I did.