autodiscover outlook error An encrypted connection to your mail server is not available

Hi,

we have 1 CAS and 1 mailbox , starting last week we received " " An encrypted connection to your mail server is not available" then it will ask to try with unencrypted but it fails again .

[PS] C:\Windows\system32>Test-OutlookWebServices -Debug
VERBOSE: [10:20:38.011 GMT] Test-OutlookWebServices : Instantiating handler with index 0 for cmdlet extension agent
"Admin Audit Log Agent".

Confirm
Continue with this operation?
[Y] Yes  [A] Yes to All  [H] Halt Command  [?] Help (default is "Y"): A
VERBOSE: [10:20:40.230 GMT] Test-OutlookWebServices : Source server: MBX1.domain.com
VERBOSE: [10:20:40.230 GMT] Test-OutlookWebServices : Source site:
domain.com/Configuration/Sites/Default-First-Site-Name
VERBOSE: [10:20:40.448 GMT] Test-OutlookWebServices : Client access monitoring user:
domain.com/Users/extest_00fc2c6c738a4
VERBOSE: [10:20:40.448 GMT] Test-OutlookWebServices : Client access monitoring user primary SMTP address:
extest_00fc2c6c738a4@domain.com
VERBOSE: [10:20:40.448 GMT] Test-OutlookWebServices : Client access monitoring organization:
VERBOSE: [10:20:40.448 GMT] Test-OutlookWebServices : Found Service Connection Point 'CAS1\CAS1' by site
'Default-First-Site-Name' with URL 'https://mail.domain.com/Autodiscover/Autodiscover.xml'.
VERBOSE: [10:20:40.448 GMT] Test-OutlookWebServices : Found Autodiscover URL
'https://mail.domain.com/Autodiscover/Autodiscover.xml' by email address 'extest_00fc2c6c738a4@domain.com'.

Confirm
Are you sure you want to perform this action?
Testing Outlook Web Services.
[Y] Yes  [A] Yes to All  [N] No  [L] No to All  [?] Help (default is "Y"): A
VERBOSE: [10:20:53.902 GMT] Test-OutlookWebServices : Autodiscover connecting to
'https://mail.domain.com/Autodiscover/Autodiscover.xml'.
VERBOSE: [10:20:53.902 GMT] Test-OutlookWebServices : Test account: extest_00fc2c6c738a4@domain.com Password: ******
VERBOSE: [10:20:53.980 GMT] Test-OutlookWebServices : Autodiscover request:
User-Agent: MBX1/Test-OutlookWebServices/extest_00fc2c6c738a4@domain.com
Content-Type: text/xml; charset=utf-8
Authorization: Negotiate
TlRMTVNTUAADAAAAGAAYAKoAAABGAUYBwgAAAAAAAABYAAAAQABAAFgAAAASABIAmAAAABAAEAAIAgAAFYKI4gYC8CMAAAAPeTC2ILCpGlSfAOwW0HToS2U
AeAB0AGUAcwB0AF8AMAAwAGYAYwAyAGMANgBjADcAMwA4AGEANABAAHAAbQBhAGgALgBtAGUAZAAuAHMAYQBQAE0AQQBIAC0ATQBCAFgAMQAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAiHFkumg/LSS51JNFPCAz6AQEAAAAAAACfXvxzzaTPAZPxg+5xBUF1AAAAAAIACABQAE0AQQBIAAEAEgBQAE0AQQBIAC0AQwBBA
FMAMQAEABYAcABtAGEAaAAuAG0AZQBkAC4AcwBhAAMAKgBQAE0AQQBIAC0AQwBBAFMAMQAuAHAAbQBhAGgALgBtAGUAZAAuAHMAYQAFABYAcABtAGEAaAAu
AG0AZQBkAC4AcwBhAAcACACfXvxzzaTPAQYABAACAAAACAAwADAAAAAAAAAAAAAAAABAAACg0yl3XH3ZL5V45Fp3vIJ7hU/cn7aiKTtFa6lcggwQJgoAEAB
47BOr8el1+MwcwSyjEmNkCQAqAEgAVABUAFAALwBtAGEAaQBsAC4AcABtAGEAaAAuAG0AZQBkAC4AcwBhAAAAAAAAAAAAAAAAAOF7f+9gI27pxQRVAxSo2C
M=
Host: mail.domain.com
Content-Length: 471
Expect: 100-continue
VERBOSE: [10:20:53.980 GMT] Test-OutlookWebServices : Autodiscover request:
<?xml version="1.0"?>
<Autodiscover xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://schemas.microsoft.com/exchange/autodiscover/outlook/requestschema/2006">
  <Request>
    <EMailAddress>extest_00fc2c6c738a4@domain.com</EMailAddress>

<AcceptableResponseSchema>http://schemas.microsoft.com/exchange/autodiscover/outlook/responseschema/2006a</AcceptableRe
sponseSchema>
  </Request>
</Autodiscover>
VERBOSE: [10:20:53.980 GMT] Test-OutlookWebServices : Autodiscover response:
request-id: 01291cf2-a38b-48cf-9204-5c60e1cb98df
Server: Microsoft-IIS/8.0
WWW-Authenticate: Negotiate,NTLM,Basic realm="mail.domain.com"
X-Powered-By: ASP.NET
X-FEServer: CAS1
Date: Mon, 21 Jul 2014 10:20:53 GMT
Content-Length: 0
VERBOSE: [10:20:53.980 GMT] Test-OutlookWebServices : Autodiscover response:
System.Net.WebException: The remote server returned an error: (401) Unauthorized.
   at System.Net.HttpWebRequest.GetResponse()
   at Microsoft.Exchange.Management.SystemConfigurationTasks.ServiceValidatorBase.InternalInvoke()
   at Microsoft.Exchange.Management.SystemConfigurationTasks.ServiceValidatorBase.Invoke()

Source                              ServiceEndpoint                     Scenario                      Result  Latency
                                                                                                                 (MS)
------                              ---------------                     --------                      ------  -------
MBX1.domain.com               mail.domain.com                    Autodiscover: Outlook Provider Failure      58
MBX1.domain.com                                                   Exchange Web Services          Skipped      0
MBX1.domain.com                                                   Availability Service           Skipped      0
MBX1.domain.com                                                   Offline Address Book           Skipped      0
VERBOSE: [10:20:53.980 GMT] Test-OutlookWebServices : Admin Audit Log: Entered Handler:OnComplete.