When I do an NS lookup on yorkshireimagescanning.co.uk
C:\>nslookup
> set querytype=soa
> yorkshireimagescanning.co.uk
Server: utdc.xxxxxx.com
Address: 172.16.1.2
Non-authoritative answer:
yorkshireimagescanning.co.uk
primary name server = ns.123-reg.co.uk
responsible mail addr = hostmaster.yorkshireimagescanning.co.uk
serial = 2013062302
refresh = 86400 (1 day)
retry = 0 (0 secs)
expire = 604800 (7 days)
default TTL = 86400 (1 day)
ns.123-reg.co.uk internet address = 212.67.202.2
Then for www.yorkshireimagescanning.co.uk:
C:\>nslookup
Default Server: utdc.xxxxxx.com
Address: 172.16.1.2
> www.yorkshireimagescanning.co.uk
Server: utdc.xxxxxx.com
Address: 172.16.1.2
Non-authoritative answer:
Name: waws-prod-am2-001.cloudapp.net
Address: 65.52.128.33
Aliases: www.yorkshireimagescanning.co.uk
yis.azurewebsites.net
waws-prod-am2-001.vip.azurewebsites.windows.net
> set querytype=soa
> www.yorkshireimagescanning.co.uk
Server: utdc.xxxxxx.com
Address: 172.16.1.2
Non-authoritative answer:
www.yorkshireimagescanning.co.uk canonical name = yis.azurewebsites.net
yis.azurewebsites.net canonical name = waws-prod-am2-001.vip.azurewebsites.windows.net
waws-prod-am2-001.vip.azurewebsites.windows.net canonical name = waws-prod-am2-001.cloudapp.net
>
This would seem to suggest that the two sites are not set up the same. WWW is set up as an alias (cname) through azure, where the other appears to be an A record through 123-reg.
Still, they are both going through the same IP address. I assume you are not doing anything in your app to restrict domain names?
Of all the domains:
yorkshireimagescanning.co.uk - Fails 404
www.yorkshireimagescanning.co.uk - Works
yis.azurewebsites.net - Works
waws-prod-am2-001.vip.azurewebsites.windows.net - Fails 404
waws-prod-am2-001.cloudapp.net - Fails 404
65.52.128.33 - Fails 404
All pointing to the same IP address.
The crux seems to lie in making an alias of yorkshireimagescanning.co.uk as well as the www. You need a CNAME reference for both of them pointing to yis.azurewebsites.net.