Cannot access a couple websites

[Kristof Provost]

On 24 Aug 2016, at 16:02, Carl Hattingh wrote:
> We are experiencing a issue which has me rather stumped.  We are using
> Freebsd 10.3-RELEASE-p7 under Hyper-V 2012 R2 as a firewall (pf), and 
> are
> unable to browse to www.amazon.com and outlook.office365.com under 
> certain
> circumstances.
>
<snip>
>
> Has anyone got any ideas on what this could be?  We'd be grateful for 
> any
> assistance.
>
You’re going to have to make a network capture between the gateway and 
the NTU device.
Ideally not from the gateway itself (because that might hide checksum 
issues).

Regards,
Kristof