Dear all,

Could you help me out with the problem.

There is Exchange 2010 server and ISA 2006 installed in the system. The problem is that users are not able to connect to Outlook when they're out of office.

Outlook anywhere is configured on Exchange 2010 and listeneres exist on ISA as well, but the issue still comes up. Frankly speaking, I haven't been working with ISA for years, perhaps I miss somethings.

ANy advice you can give me to resolve this issue?

Thank you in advance

Did you test Outlook anywhere from internal network?
If not please test that first.  if it works you will have to make sure your HTTP/HTTPs traffic is passing through your firewall.
Force outlook to use HTTPS (outlook anywhere) from internal network by ticking both tick boxes as below.

Open Outlook using the command
outlook.exe /rpcdiag
And check whether you see something like below in connection status window when you open outlook . 
Server:                    Type:                       Con:               
fs01.domain.local      Email                    HTTPS    
fs01.domain.local      Email                    HTTPS    

Please check Outlook connectivity from https://testconnectivity.microsoft.com/ a

Hello,

I'm trying to connect from another network and here is the thing that I have:

server name:                                type:                          conn:

exchangeserver@mydomain.com     Directory                     -----

exchangeserver@mydomain.com      Directory                  -----

exchangeserver@mydomain.com      mail                           -----

exchangeserver@mydomain.com      Referal                      -----

I would recommend testing via:

https://testconnectivity.microsoft.com/

And see what errors you get.

Did you try from your inter network which is your internal domain network.?
If not please try from that.

Did you try using   https://testconnectivity.microsoft.com/ ?
if not please do that and post the result

If it is not working from internal network you could try reinstalling the RPC Proxy component.
Below are the steps
Disable Outlook Anywhere from EMC
Remove RPC proxy component using the command: servermanagercmd -r rpc-over-http-proxy
Reboot the server
Install RPC proxy component using the command: servermanagercmd -i rpc-over-http-proxy
Enable Outlook Anywhere
Restart Microsoft Active Directory Topology service
Check if the issue still exists
The reinstallation of the RPC Proxy component should solve the problem.

Here is a reference article on how to enable outlook anywhere
http://exchangeserverpro.com/how-to-configure-exchange-server-2010-outlook-anywhere/

Thank you for your answer:

these are the results:

 Testing Outlook connectivity.

 The Microsoft Connectivity Analyzer is attempting to test Autodiscover for mailbox@mydomain.com.
  Testing Autodiscover failed.
  
 Additional Details
  
Elapsed Time: 6272 ms.
  
 Test Steps
  
 Attempting each method of contacting the Autodiscover service.
  The Autodiscover service couldn't be contacted successfully by any method.
  
 Additional Details
  
Elapsed Time: 6272 ms.
  
 Test Steps
  
 Attempting to test potential Autodiscover URL https://mydomain.com:443/Autodiscover/Autodiscover.xml
  Testing of this potential Autodiscover URL failed.
  
 Additional Details
  
Elapsed Time: 385 ms.
  
 Test Steps
  
 Attempting to resolve the host name mydomain.com in DNS.
  The host name resolved successfully.
  
 Additional Details
  
IP addresses returned: 109.123.72.130
Elapsed Time: 7 ms.
 Testing TCP port 443 on host mydomain.com to ensure it's listening and open.
  The port was opened successfully.
  
 Additional Details
  
Elapsed Time: 123 ms.
 Testing the SSL certificate to make sure it's valid.
  The SSL certificate failed one or more certificate validation checks.
  
 Additional Details
  
Elapsed Time: 254 ms.
  
 Test Steps
  
 The Microsoft Connectivity Analyzer is attempting to obtain the SSL certificate from remote server mydomain.com on port 443.
  The Microsoft Connectivity Analyzer successfully obtained the remote SSL certificate.
  
 Additional Details
  
Remote Certificate Subject: CN=cpanel35.uk2.ne, OU=PositiveSSL, OU="Hosted by HOSTING SERVICES, INC.", OU=Domain Control Validated, Issuer: CN=COMODO RSA Domain Validation Secure Server CA, O=COMODO CA Limited, L=Salford, S=Greater Manchester, C=GB.
Elapsed Time: 232 ms.
 Validating the certificate name.
  Certificate name validation failed.
   Tell me more about this issue and how to resolve it
  
 Additional Details
  
Host name mydomain.com doesn't match any name found on the server certificate CN=cpanel35.uk2.net, OU=PositiveSSL, OU="Hosted by HOSTING SERVICES, INC.", OU=Domain Control Validated.
Elapsed Time: 0 ms.
 Attempting to test potential Autodiscover URL https://autodiscover.mydomain.com:443/Autodiscover/Autodiscover.xml
  Testing of this potential Autodiscover URL failed.
  
 Additional Details
  
Elapsed Time: 4592 ms.
  
 Test Steps
  
 Attempting to resolve the host name autodiscover.mydomain.com in DNS.
  The host name resolved successfully.
  
 Additional Details
  
IP addresses returned: 37.151.41.234
Elapsed Time: 6 ms.
 Testing TCP port 443 on host autodiscover.mydomain.com to ensure it's listening and open.
  The port was opened successfully.
  
 Additional Details
  
Elapsed Time: 391 ms.
 Testing the SSL certificate to make sure it's valid.
  The SSL certificate failed one or more certificate validation checks.
  
 Additional Details
  
Elapsed Time: 4193 ms.
  
 Test Steps
  
 The Microsoft Connectivity Analyzer is attempting to obtain the SSL certificate from remote server autodiscover.mydomain.com on port 443.
  The Microsoft Connectivity Analyzer successfully obtained the remote SSL certificate.
  
 Additional Details
  
Remote Certificate Subject: CN=mail2.mydomain.com, OU=IT dept., O=domain, L=city, S=city, C=KZ, Issuer: CN=EXCHANGESERVER-CA, DC=domain, DC=COM.
Elapsed Time: 4157 ms.
 Validating the certificate name.
  The certificate name was validated successfully.
  
 Additional Details
  
Host name autodiscover.mydomain.com was found in the Certificate Subject Alternative Name entry.
Elapsed Time: 0 ms.
 Certificate trust is being validated.
  Certificate trust validation failed.
  
 Test Steps
  
 The Microsoft Connectivity Analyzer is attempting to build certificate chains for certificate CN=mail2.mydomain.com, OU=IT dept., O=domain, L=city, S=city, C=KZ.
  A certificate chain couldn't be constructed for the certificate.
  
 Additional Details
  
The certificate chain couldn't be built. You may be missing required intermediate certificates.
Elapsed Time: 15 ms.
 Attempting to contact the Autodiscover service using the HTTP redirect method.
  The attempt to contact Autodiscover using the HTTP Redirect method failed.
  
 Additional Details
  
Elapsed Time: 936 ms.
  
 Test Steps
  
 Attempting to resolve the host name autodiscover.mydomain.com in DNS.
  The host name resolved successfully.
  
 Additional Details
  
IP addresses returned: 37.151.41.234
Elapsed Time: 6 ms.
 Testing TCP port 80 on host autodiscover.mydomain.com to ensure it's listening and open.
  The port was opened successfully.
  
 Additional Details
  
Elapsed Time: 321 ms.
 The Microsoft Connectivity Analyzer is checking the host autodiscover.mydomain.com for an HTTP redirect to the Autodiscover service.
  The Microsoft Connectivity Analyzer failed to get an HTTP redirect response for Autodiscover.
  
 Additional Details
  
A Web exception occurred because an HTTP 404 - NotFound response was received from IIS6.
HTTP Response Headers:
Connection: Keep-Alive
Proxy-Connection: Keep-Alive
Content-Length: 1635
Content-Type: text/html
Date: Wed, 03 Jun 2015 11:43:30 GMT
Server: Microsoft-IIS/6.0
Via: 1.1 SRSEFT02
X-Powered-By: ASP.NET
Elapsed Time: 608 ms.
 Attempting to contact the Autodiscover service using the DNS SRV redirect method.
  The Microsoft Connectivity Analyzer failed to contact the Autodiscover service using the DNS SRV redirect method.
  
 Additional Details
  
Elapsed Time: 241 ms.
  
 Test Steps
  
 Attempting to locate SRV record _autodiscover._tcp.mydomain.com in DNS.
  The Autodiscover SRV record wasn't found in DNS.
   Tell me more about this issue and how to resolve it
  
 Additional Details
  
Elapsed Time: 241 ms.
 Checking if there is an autodiscover CNAME record in DNS for your domain 'mydomain.com' for Office 365.
  Failed to validate autodiscover CNAME record in DNS. If your mailbox isn't in Office 365, you can ignore this warning.
   Tell me more about this issue and how to resolve it
  
 Additional Details
  
There is no Autodiscover CNAME record for your domain 'mydomain.com'.
Elapsed Time: 116 ms.

Please make sure you have configured autodiscover URLs correctly.

Do you have an A record autodiscover.domain.com in your external DNS. If not please create it.

Please check my article to configure your URLs properly.

http://social.technet.microsoft.com/wiki/contents/articles/26721.oof-autodiscover-and-outlook-certificate-issues.aspx