Howdy,

We have Exchange 2013 and used to be able to check some email addresses via IMAP but it is no longer working.  If I go to the exchange server itself and to a Telnet Localhost 143 I get the expected OK response.  However, if I telnet to it from any other server or workstation I just get no response at all.  I just get a flashing cursor with a blank screen.  If I click or tap anything it just takes me back to the C prompt.

I've tried restart the IMAP service but that had no effect.  Does anyone know what might have changed or where I can look to see if the connection is getting through or not?  We don't have any firewalls turned on on these machines.

Thanks!

If it works on the server itself, then it has to be something blocking the connection - AV software, firewall for example.

If you have AV on the server, then check it has the correct exclusions on it.

The behaviour you have posted is classic blocking behaviour.

The Windows Firewall should really be enabled, Microsoft don't test their products with the Windows Firewall disabled.

Simon.

If it works on the server itself, then it has to be something blocking the connection - AV software, firewall for example.

If you have AV on the server, then check it has the correct exclusions on it.

The behaviour you have posted is classic blocking behaviour.

The Windows Firewall should really be enabled, Microsoft don't test their products with the Windows Firewall disabled.

Hi,

Please run the following command to check the IMAP settings in server side:
Get-IMAPSettings | fl

In client side, is there any error descriptions? Additionally, please collect any related event logs from server side for further analysis.

Regards,

Hi,

Please run the following command to check the IMAP settings in server side:
Get-IMAPSettings | fl

In client side, is there any error descriptions? Additionally, please collect any related event logs from server side for further analysis.

Howdy,

We have a CAS server and a Mailbox server.  I ran the command from the CAS server and here's the output I got:

RunspaceId                        : 9dfb81e2-63f0-4b62-a1ce-413f4e1053c2
ProtocolName                      : IMAP4
Name                              : 1
MaxCommandSize                    : 10240
ShowHiddenFoldersEnabled          : False
UnencryptedOrTLSBindings          : {[::]:143, 0.0.0.0:143}
SSLBindings                       : {[::]:993, 0.0.0.0:993}
InternalConnectionSettings        : {MailboxServer.Domain.net:993:SSL, MailboxServer.Domain.net:143:TLS}
ExternalConnectionSettings        : {}
X509CertificateName               : MailboxServer
Banner                            : The Microsoft Exchange IMAP4 service is ready.
LoginType                         : SecureLogin
AuthenticatedConnectionTimeout    : 00:30:00
PreAuthenticatedConnectionTimeout : 00:01:00
MaxConnections                    : 2147483647
MaxConnectionFromSingleIP         : 2147483647
MaxConnectionsPerUser             : 16
MessageRetrievalMimeFormat        : BestBodyFormat
ProxyTargetPort                   : 9933
CalendarItemRetrievalOption       : iCalendar
OwaServerUrl                      : 
EnableExactRFC822Size             : False
LiveIdBasicAuthReplacement        : False
SuppressReadReceipt               : False
ProtocolLogEnabled                : False
EnforceCertificateErrors          : False
LogFileLocation                   : D:\Program Files\Microsoft\Exchange Server\V15\Logging\Imap4
LogFileRollOverSettings           : Daily
LogPerFileSizeQuota               : 0 B (0 bytes)
ExtendedProtectionPolicy          : None
EnableGSSAPIAndNTLMAuth           : True
Server                            : MailboxServer
AdminDisplayName                  : 
ExchangeVersion                   : 0.10 (14.0.100.0)
DistinguishedName                 : CN=1,CN=IMAP4,CN=Protocols,CN=MailboxServer,CN=Servers,CN=Exchange Administrative 
                                    Group (FYDIBOHF23SPDLT),CN=Administrative Groups,CN=Domain,CN=Microsoft 
                                    Exchange,CN=Services,CN=Configuration,DC=Domain,DC=net
Identity                          : MailboxServer\1
Guid                              : 40209128-4ee0-4fb3-87a1-0538f06ba69c
ObjectCategory                    : Domain.net/Configuration/Schema/ms-Exch-Protocol-Cfg-IMAP-Server
ObjectClass                       : {top, protocolCfg, protocolCfgIMAP, protocolCfgIMAPServer}
WhenChanged                       : 3/12/2014 7:22:37 PM
WhenCreated                       : 3/12/2014 7:22:34 PM
WhenChangedUTC                    : 3/13/2014 12:22:37 AM
WhenCreatedUTC                    : 3/13/2014 12:22:34 AM
OrganizationId                    : 
Id                                : MailboxServer\1
OriginatingServer                 : DomainController.Domain.net
IsValid                           : True
ObjectState                       : Unchanged

I checked event viewer on both systems and didn't find anything.

I just ran the Test-ImapConnectivity commend from our CAS server and got an error that:

Service MSExchangeIMAP4 was not found on computer....

The computer listed is the Mailbox Server and not the CAS server.  On the CAS server I see MSExchangeImap4 running and on the MBX server I see MSExchangeIMAP4BE running which seems right to me...

Not sure if that helps.

Thanks.

OK, we got this figured out.  Our Exchange Admin finally figured out that somethign was messed up with the IMAP Proxy in the exchange system somewhere.

When he did a:Get-ServerComponentState Identity [servername], it showed the proxy as inactive.

He they had to use: Set-ServerComponentState Identity [servername] State Active Requester HealthAPI Component IMAPProxy to get everything up and running again and now it all seems to be working fine.