Outlook anywhere problem

Hi,

i have big trouble with outlook anywhere. My exchange 2013 farm contains two cas server with load balancer and two mailbox server for dag. OWA works fine certificate is implemented but i can not connect outlook. Remote connectivity analyzer say this error:

Attempting to ping RPC proxy mail.domain.com.
RPC Proxy can't be pinged.
Additional Details
A Web exception occurred because an HTTP 404 - NotFound response was received from Unknown.


Address "mail.mydomain.com" is aligned to load balancer with contain two cas servers.

(mydomain.com isn't my domain :-) - it is used only for this example)

Confioguration from cas1:

ExternalHostname : mail.mydomain.com
InternalHostname : mail.mydomain.com
ExternalClientAuthenticationMethod : Basic
InternalClientAuthenticationMethod : Basic
IISAuthenticationMethods : {Basic}
XropUrl :
ExternalClientsRequireSsl : True
InternalClientsRequireSsl : True
MetabasePath : IIS://CAS1.mydomain.com /W3SVC/1/ROOT/Rpc
Path : C:\Exchange Server\V15\FrontEnd\HttpProxy\rpc
ExtendedProtectionTokenChecking : None
ExtendedProtectionFlags : {}
ExtendedProtectionSPNList : {}
AdminDisplayVersion : Version 15.0 (Build 516.32)
Server : CAS1
AdminDisplayName :
ExchangeVersion : 0.20 (15.0.0.0)
Name : Rpc (Default Web Site)
DistinguishedName : CN=Rpc (Default Web Site),CN=HTTP,CN=Protocols,CN=CAS1,CN=Servers,CN=Exchange Adm
inistrative Group (FYDIBOHF23SPDLT),CN=Administrative Groups,CN=mydomain,CN=Micro
soft Exchange,CN=Services,CN=Configuration,DC= mydomain,DC=cz
Identity : CAS1\Rpc (Default Web Site)
Guid : 1227e98f-8c9f-4389-b8e0-9b7f9eb896b5
ObjectCategory : mydomain.cz/Configuration/Schema/ms-Exch-Rpc-Http-Virtual-Directory
ObjectClass : {top, msExchVirtualDirectory, msExchRpcHttpVirtualDirectory}
WhenChanged : 6. 3. 2013 18:51:54
WhenCreated : 1. 2. 2013 11:31:34
WhenChangedUTC : 6. 3. 2013 17:51:54
WhenCreatedUTC : 1. 2. 2013 10:31:34
OrganizationId :
OriginatingServer : ad01.mydomain.com
IsValid : True
ObjectState : Changed

Thank you for any idea