[Users] Disable IPv6

[Colin Leroy-Mira]

> I am testing out other Linux OS' in virtual machines, which only
> provides IPv4. One of the IMAP servers accessed, pretty much forces an
> IPv6 connection and with Claws, it's been hit-or-miss. 99% of the time,
> it's a miss and the Network Log always shows 'connection refused'.
> 
> In order to access the same IMAP server using Thunderbird, this required
> going into its Preferences Editor and disabling IPv6.

Easiest way is to do it on the OS level if there's no ipv6 connectivity: 

echo 1 > /proc/sys/net/ipv6/conf/all/disable_ipv6

add net.ipv6.conf.all.disable_ipv6 = 1 to /etc/sysctl.conf to make it stick across reboots.

HTH,

-- 
Colin