I have everything working for PC's internal and external, but for Macs I cant connect,  when I launch any app it looks like it tries to connect then I get "the gateway failed to connect with the message : 404 Not Found "

Hi,

After referring to your issue, if you are using RD Gateway then I can suggest you to check setting under RD gateway. You can uncheck the option Bypass RD Gateway server for local address and check the result. By unchecking that client connection will not try to connect to RD gateway for local address. Please check below snapshot and link for more information.

Configure Remote Desktop Gateway Settings
http://technet.microsoft.com/en-us/library/cc772479.aspx

 
Hope it helps!
Regards.

I unchecked the setting but sadly it didn't work.  I even rebooted the server just in case.

The thing is it used to work.  I fixed it until it broke :(

I need this asap...im at my wits end...

Can someone please look over my settings?  

Everything works on a PC.  Its iOS devices an Macs that keep giving me issues.....

Hi,

Here trying to provide you some more setting where you can try to create a new RD Gateway-managed computer group that contains both the NetBIOS names and the fully qualified domain names (FQDNs) of the RD Session Host servers or the RD Session Host server farm and it must match in your device.

Apart there are few more setting related to RD Gateway you can check as below:

1.  The RD Gateway server should be configured to allow connections from all supported clients
2.  The RD Gateway server should be configured to allow new connections
3.  The Remote Desktop Users group on the RD Session Host server must contain domain users or groups
4.  Members of an RD Gateway server farm should be available on the network and configured identically

For more information you can go through Best Practices Analyzer for RDS where you can find setting related to RD Gateway.

Best Practices Analyzer for Remote Desktop Services: Configuration
http://technet.microsoft.com/en-us/library/dd378949(v=ws.10).aspx

Hope it helps!
Regards.

thanks, ive tried those suggestions.  

Does my RDS Gateway have to be an external URL?

Actually, I'm not entirely sure what the first part here means

Here trying to provide you some more setting where you can try to create a new RD Gateway-managed computer group that contains both the NetBIOS names and the fully qualified domain names (FQDNs) of the RD Session Host servers or the RD Session Host server farm and it must match in your device.

What are you suggesting exactly?

I think I know what you mean...but I am allowing users to connect to any network resources.  Do I still need to do that?