Autodiscover URL returning error

Question

I have the AutoDiscover rule created in TMG and and it tests fine within the TMG console.
However, when I hit the external URL lyncdiscover.domain.com I get this back:
Unable to download / from lyncdiscover.domain.com
Unable to open the Internet site.  The requested site is either unavailable or cannot be found.
The rule is being hit if I filter the logging.  There just seems to be some problem with it downloading the autodiscovery info.
Anyone else run into this?

Answer 1

Here is my config that works.  I have split brain DNS, FE, Edge, and TMG with a third party firewall and TMG as the backend firewall.  I use an external web service name different than the internal pool.
Identity                        : WebServer:<pool>.<External-Domain.com>
FileStore                       : FileStore:<FESERVER>.<AD-DOMAIN.net>
UserServer                      : UserServer:<pool>.<External-Domain.com>
PrimaryHttpPort                 : 80
PrimaryHttpsPort                : 443
ExternalHttpPort                : 8080
ExternalHttpsPort               : 4443
PublishedPrimaryHttpPort        : 80
PublishedPrimaryHttpsPort       : 443
PublishedExternalHttpPort       : 80
PublishedExternalHttpsPort      : 443
ReachPrimaryPsomServerPort      : 8060
ReachExternalPsomServerPort     : 8061
AppSharingPortStart             : 49152
AppSharingPortCount             : 16383
McxSipPrimaryListeningPort      : 5086
McxSipExternalListeningPort     : 5087
LIServiceInternalUri            :
https://<pool>.<External-Domain.com>/locationinformation/liservice.svc
ABHandlerInternalUri            :
https://<pool>.<External-Domain.com>/abs/handler
ABHandlerExternalUri            :
https://lyncweb.<External-Domain.com>/abs/handler
DLExpansionInternalUri          :
https://<pool>.<External-Domain.com>/groupexpansion/service.svc
DLExpansionExternalUri          :
https://lyncweb.<External-Domain.com>/groupexpansion/service.svc
CAHandlerInternalUri            :
https://<pool>.<External-Domain.com>/CertProv/CertProvisioningService.svc
CAHandlerInternalAnonUri        :
http://<pool>.<External-Domain.com>/CertProv/CertProvisioningService.svc
CollabContentInternalUri        :
https://<pool>.<External-Domain.com>/CollabContent
CollabContentExternalUri        :
https://lyncweb.<External-Domain.com>/CollabContent
CAHandlerExternalUri            :
https://lyncweb.<External-Domain.com>/CertProv/CertProvisioningService.svc
DeviceUpdateDownloadInternalUri :
https://<pool>.<External-Domain.com>/RequestHandler/ucdevice.upx
DeviceUpdateDownloadExternalUri :
https://lyncweb.<External-Domain.com>/RequestHandlerExt/ucdevice.upx
DeviceUpdateStoreInternalUri    :
http://<pool>.<External-Domain.com>/RequestHandler/Files
DeviceUpdateStoreExternalUri    :
https://lyncweb.<External-Domain.com>/RequestHandlerExt/Files
RgsAgentServiceInternalUri      :
https://<pool>.<External-Domain.com>/RgsClients/AgentService.svc
RgsAgentServiceExternalUri      :
https://lyncweb.<External-Domain.com>/RgsClients/AgentService.svc
MeetExternalUri                 :
https://lyncweb.<External-Domain.com>/Meet
DialinExternalUri               :
https://lyncweb.<External-Domain.com>/Dialin
CscpInternalUri                 :
https://<pool>.<External-Domain.com>/Cscp
ReachExternalUri                :
https://lyncweb.<External-Domain.com>/Reach
ReachInternalUri                :
https://<pool>.<External-Domain.com>/Reach
WebTicketExternalUri            :
https://lyncweb.<External-Domain.com>/WebTicket/WebTicketService.svc
WebTicketInternalUri            :
https://<pool>.<External-Domain.com>/WebTicket/WebTicketService.svc
McxServiceExternalUri           :
https://lyncweb.<External-Domain.com>/Mcx/McxService.svc
McxServiceInternalUri           :
https://<pool>.<External-Domain.com>/Mcx/McxService.svc
AutodiscoverServiceExternalUri  :
https://lyncweb.<External-Domain.com>/Autodiscover/AutodiscoverService.svc/root
AutodiscoverServiceInternalUri  :
https://<pool>.<External-Domain.com>/Autodiscover/AutodiscoverService.svc/root
ExternalFqdn                    : lyncweb.<External-Domain.com>
InternalFqdn                    :
DependentServiceList            : {Registrar:<pool>.<External-Domain.com>, ConferencingServer:<pool>.<External-Domain.com>}
ServiceId                       : 1-WebServices-1
SiteId                          : Site:ABC
PoolFqdn                        : <pool>.<External-Domain.com>
Version                         : 5
Role                            : WebServer