People Picker Port Tester Failed to DNS Test

I have a Problem with People Picker in Sharepoint 2013,

I have One Domain Server with windows server 2008 and one Server for MSSQL 2012 and Sharepoint 2013. "we have a small network with 14 users at max". Also we Have Kerio in network for Control internet sharing.

My Problem is i can't find any user with People Picker but i can select "Everyone" | "Domain Admin" and etc.

I test my Ports and DNS With People Picker Port Tester: https://peoplepicker.codeplex.com/

And unfortunately the DNS Test section returns "no dns found" but all my ports can get connected. "I Allowed Ports in Firewall in both Servers"

I also find this error log when i trying to find users in AD with PP:

12/17/2014 00:37:20.23  w3wp.exe (0x1728)   0x1A88  SharePoint Foundation   General 72e7        Medium  Error in searching user 'Some-User' :     System.DirectoryServices.DirectoryServicesCOMException (0x80072020): An operations error occurred.       at System.DirectoryServices.SearchResultCollection.ResultsEnumerator.MoveNext()     at Microsoft.SharePoint.WebControls.PeopleEditor.SearchFromGC(SPActiveDirectoryDomain domain, String strFilter, String[] rgstrProp, Int32 nTimeout, Int32 nSizeLimit, SPUserCollection spUsers, ArrayList& rgResults)     at Microsoft.SharePoint.Utilities.SPUserUtility.SearchAgainstAD(String input, Boolean useUpnInResolve, SPActiveDirectoryDomain domainController, SPPrincipalType scopes, SPUserCollection usersContainer, Int32 maxCount, String customQuery, String customFilter, TimeSpan searchTimeout, Boolean& reachMaxCount)     at Microsoft.SharePoint.Utilities.SPActiveDirectoryPrincipalResolver.SearchPrincipals(String input, SPPrincipalType scopes, SPPrincipalSource sources, SPUserCollection usersContainer, Int32 maxCount, Boolean& reachMaxCount)     at Microsoft.SharePoint.Utilities.SPUtility.SearchPrincipalFromResolvers(List`1 resolvers, String input, SPPrincipalType scopes, SPPrincipalSource sources, SPUserCollection usersContainer, Int32 maxCount, Boolean& reachMaxCount, Dictionary`2 usersDict).   1c99d69c-fd6c-d086-2e71-662fc7a6ad20

Thanks for Help.