Exchange 2010 can't send or receive email with attachments.

Question

Hello,
We have an Exchange 2010 server, running under Windows 2008R2. Both the server and Exchange are current for Windows and Exchange updates. Exchange is on SP3 installed about a month ago with no errors reported in the event logs.
The problem is that attachments over about 1 MB do not send or receive and no error message is returned. If I send an email message with a 3 MB attachment to myself, it reports as sent in Outlook. On the Exchange server the message queue shows nothing in
the queue. I try to use Exchange mail flow tracking tool and it hangs when selecting “messages received from” option. I gave up waiting after 5 minutes for the display to populate.
As the server is set attachments should be able to send and receive up to 20 MB.
I checked and verified all settings I could find related to this. I checked with the Exchange Management Console per the following article:
http://www.msexchange.org/articles-tutorials/exchange-server-2010/management-administration/managing-limits-exchange-server-2010-part1.html
I also checked using the Exchange Power Shell using the following article:
http://eightwone.com/2010/09/29/exchange-message-size-limits/
Both show that all settings are suitable. Details are below
I would appreciate feedback on this problem.
Thank you!
Details from the articles noted above:
First test was to attach a 3 mb text file in Outlook sent from my in house account to my in house account. After 5 minutes the test message was not received nor was there an error message returned.
Checked The Exchange server mail queue and there was nothing in the queue. Checked the Exchange mail flow tracking tool and it hung when selecting “messages received from” option.
Reviewed and verified settings per the following 2 articles:
Article #1
http://www.msexchange.org/articles-tutorials/exchange-server-2010/management-administration/managing-limits-exchange-server-2010-part1.html
Organization Configuration>Hub Transport>General Settings>Global Settings>Transport Settings set to max receive size (KB) = 20480
Settings set to max send size (KB) = 20480
Organization Configuration> Hub Transport> Send Connectors tab.
Maximum message size (KB) set to 20480
Exchange Management Console> Server Configuration> Hub Transport> and then on the right side, select the desired server.
A list of all Receive Connectors will be shown below
There are 3 receive Connectors
#1) named Client XXXXXXXXXX
Maximum message size (KB) set to 20480
#2) named Default  XXXXXXXXXX
Maximum message size (KB) set to 20480
#3) named relay
Maximum message size (KB) set to 20480
Use Exchange Management Shell to check settings
#1) Get-ADSite
Returns:
Name                           HubSiteEnabled
Default-First-Site-Name        False
#2) Get-ADSiteLink
Name                      ADCost     ExchangeCost    Sites
DEFAULTIPSITELINK         100                        {xxxx.local/Configuration/Si...
#3) Get-ADSiteLink | select Max*
MaxMessageSize
unlimited
Exchange Management Console>Expand Organization Configuration>Click on Hub Transport item>Click on Transport Rules tab
No rules
Article #2 
http://eightwone.com/2010/09/29/exchange-message-size-limits/
COMMAND: Get –TransportConfig
results:
ClearCategories                     : True
ConvertDisclaimerWrapperToEml       : False
DSNConversionMode                   : UseExchangeDSNs
ExternalDelayDsnEnabled             : True
ExternalDsnDefaultLanguage          :
ExternalDsnLanguageDetectionEnabled : True
ExternalDsnMaxMessageAttachSize     : 10 MB (10,485,760 bytes)
ExternalDsnReportingAuthority       :
ExternalDsnSendHtml                 : True
ExternalPostmasterAddress           :
GenerateCopyOfDSNFor                : {}
HygieneSuite                        : Standard
InternalDelayDsnEnabled             : True
InternalDsnDefaultLanguage          :
InternalDsnLanguageDetectionEnabled : True
InternalDsnMaxMessageAttachSize     : 10 MB (10,485,760 bytes)
InternalDsnReportingAuthority       :
InternalDsnSendHtml                 : True
InternalSMTPServers                 : {}
JournalingReportNdrTo               : <>
LegacyJournalingMigrationEnabled    : False
MaxDumpsterSizePerDatabase          : 18 MB (18,874,368 bytes)
MaxDumpsterTime                     : 7.00:00:00
MaxReceiveSize                      : 20 MB (20,971,520 bytes)
MaxRecipientEnvelopeLimit           : 500
MaxSendSize                         : 20 MB (20,971,520 bytes)
MigrationEnabled                    : False
OpenDomainRoutingEnabled            : False
Rfc2231EncodingEnabled              : False
ShadowHeartbeatRetryCount           : 12
ShadowHeartbeatTimeoutInterval      : 00:15:00
ShadowMessageAutoDiscardInterval    : 2.00:00:00
ShadowRedundancyEnabled             : True
SupervisionTags                     : {Reject, Allow}
TLSReceiveDomainSecureList          : {}
TLSSendDomainSecureList             : {}
VerifySecureSubmitEnabled           : False
VoicemailJournalingEnabled          : True
HeaderPromotionModeSetting          : NoCreate
Xexch50Enabled                      : True
COMMAND: 
Set-TransportConfig –MaxReceiveSize 20MB –MaxSendSize 20MB
C:\Windows\system32>Set-TransportConfig -MaxReceiveSize 20MB -MaxSendSize 20MB
WARNING: The command completed successfully but no settings of 'Transport Settings' have been modified.
COMMAND: 
Get-SendConnector
Identity                                AddressSpaces                         
 Enabled
Internet                                {SMTP:*;1}                             
True
COMMAND: 
Set-SendConnector -Identity Internet -MaxMessageSize 20MB
WARNING: The command completed successfully but no settings of 'Internet' have been modified.
COMMAND: 
Get-ReceiveConnector
Identity                                Bindings                                Enabled
XXXXXXXXXX\Default XXXXXXXXXX           {0.0.0.0:25}                           
True
XXXXXXXXXX \Client XXXXXXXXXX     {:::587, 0.0.0.0:587}                   True
XXXXXXXXXX \relay                        {0.0.0.0:25}                           
True
COMMAND: 
Get-ReceiveConnector | fl Identity,MaxMessageSize
Identity       : XXXXXXXXXX \Default XXXXXXXXXX
MaxMessageSize : 20 MB (20,971,520 bytes)
Identity       : XXXXXXXXXX \Client XXXXXXXXXX
MaxMessageSize : 20 MB (20,971,520 bytes)
Identity       : XXXXXXXXXX \relay
MaxMessageSize : 20 MB (20,971,520 bytes)
COMMAND: 
Get-AdSiteLink | fl Name,*max*
Name           : DEFAULTIPSITELINK
MaxMessageSize : unlimited
COMMAND: 
Get-RoutingGroupConnector <ConnectorID> | FL Name, *Max*
No routing group connectors are installed
Individual
Recipient Configuration > Mailbox>Properties of the User> Activate tab Mail Flow Settings> Properties>Message Size Restrictions settings:
Set to 20480 for send and receive for all.
Re-tested and had the same problem. 
Post on Technet.

Answer 1

ExchangeITPro,
Thank you for your reply.
>what SP are you at?
As noted in the first paragraph: "We have an Exchange 2010 server, running under Windows 2008R2. Both
the server and Exchange are current for Windows and Exchange updates. Exchange is on SP3 installed about a month ago with no errors reported in the event logs."
>try restarting the transport services.
Done previously as well as the entire server. No change.