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Displaying all the Message Size limits via Script

Message Size limits in Exchange can be set at a number of different levels to give you the flexibility that we as IT people yearn for. This flexibility does come at a cost if you have to answer that quick question about what limits you actually have in your Exchange Org. If you want to work out what the effective message size limit was for one particular user via the GUI you would first have to check

Global Setting under Message Delivery
The Setting on Each Connector the mail could flow though
The Setting on Each of the SMTP Virtual Servers mail could flow though
The Setting on the Actual user account

(This is all documented in Q322679 )

So what I’ve put together is a script that queries all these setting from active directory and outputs the results to the console. The Script logic is pretty simple if queries each of the different objects types in the configuration partition and then accesses the limit property if they have been set and display it back to console. The first query hits the Global settings the second returns all the connector the third returns the virtual servers and the last 2 query looks for all the users that have had individual message size limit configured. These last two queries may look a bit odd but by default the message size limits on a user account would not be set so doing a query where (delivContLength=*) will only return those account where this property has been set.

One thing to remember here is this shows all the native places where message limits may have been configured a lot of third party software such a AV/SPAM/Content-filtering application may also implement this functionality.

I’ve put a downloadable copy of the script here the code looks like

set conn = createobject("ADODB.Connection")
set com = createobject("ADODB.Command")
Set iAdRootDSE = GetObject("LDAP://RootDSE")
strNameingContext = iAdRootDSE.Get("configurationNamingContext")
strDefNamingContext = iAdRootDSE.Get("defaultNamingContext")
Conn.Provider = "ADsDSOObject"
Conn.Open "ADs Provider"
gsQuery = "<LDAP://" & strNameingContext & ">;(objectCategory=msExchMessageDeliveryConfig);name,distinguishedName;subtree"
Com.ActiveConnection = Conn
Com.CommandText = gsQuery
Set Rs = Com.Execute
Wscript.echo "Global Settings - Message Delivery Properties"
Wscript.echo
While Not Rs.EOF
strconfcont = "LDAP://" & rs.fields("distinguishedName")
set ccConfig = getobject(strconfcont)
wscript.echo "Sending Message Size Limit: " & ccConfig.submissionContLength & "
KB"
wscript.echo "Recieving Message Size Limit: " & ccConfig.delivContLength & " KB"
wscript.echo "Recipient Limits: " & ccConfig.msExchRecipLimit
rs.movenext
wend
Wscript.echo
Wscript.echo "Connector Settings"
wscript.echo
vsQuery = "<LDAP://" & strNameingContext &
">;(objectCategory=msExchRoutingSMTPConnector);name,distinguishedName;subtree"
Com.ActiveConnection = Conn
Com.CommandText = vsQuery
Set Rs = Com.Execute
While Not Rs.EOF
strconnect = "LDAP://" & rs.fields("distinguishedName")
set cnCconnect = getobject(strconnect)
wscript.echo "Connector Name:" & cnCconnect.cn
wscript.echo "Max Message Size Limit:" & cnCconnect.delivContLength & " KB"
wscript.echo
rs.movenext
wend
Wscript.echo
Wscript.echo "SMTP Virtual Server Settings"
wscript.echo
vsQuery = "<LDAP://" & strNameingContext &
">;(objectCategory=protocolCfgSMTPServer);name,distinguishedName;subtree"
Com.ActiveConnection = Conn
Com.CommandText = vsQuery
Set Rs = Com.Execute
While Not Rs.EOF
strstmsrv = "LDAP://" & rs.fields("distinguishedName")
set svsSmtpserver = getobject(strstmsrv)
wscript.echo "ServerName:" &
mid(svsSmtpserver.distinguishedName,instr(svsSmtpserver.distinguishedName,"CN=Protocols,")+16,instr(svsSmtpserver.distinguishedName,",CN=Servers")-(instr(svsSmtpserver.distinguishedName,"CN=Protocols,")+16))
wscript.echo "Virtual Server Name:" & svsSmtpserver.adminDisplayName
wscript.echo "Max Message Size Limit:" &
svsSmtpserver.msExchSmtpMaxMessageSize/1024 & " KB"
wscript.echo "Recipient Limits:" & svsSmtpserver.msExchSmtpMaxRecipients
wscript.echo
rs.movenext
wend
Wscript.echo
Wscript.echo "Users with Sending Limits"
wscript.echo
srquery = "<LDAP://" & strDefNamingContext &
">;(&(&(objectCategory=Person)(objectclass=user)(submissionContLength=*)));name,displayname,distinguishedName
,submissionContLength;subtree"
Com.ActiveConnection = Conn
Com.CommandText = srquery
Set Rs = Com.Execute
While Not Rs.EOF
wscript.echo "User:" & rs.fields("displayname")
wscript.echo "Sending Message Size Limit:" & rs.fields("submissionContLength") &
" KB"
wscript.echo
rs.movenext
wend
Wscript.echo
Wscript.echo "Users with Receiving Limits"
wscript.echo
srquery = "<LDAP://" & strDefNamingContext &
">;(&(&(objectCategory=Person)(objectclass=user)(delivContLength=*)));name,displayname,distinguishedName,delivContLength;subtree"
Com.ActiveConnection = Conn
Com.CommandText = srquery
Set Rs = Com.Execute
While Not Rs.EOF
wscript.echo "User:" & rs.fields("displayname")
wscript.echo "Receiving Message Size Limit:" & rs.fields("delivContLength") & "
KB"
wscript.echo
rs.movenext
wend

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All sample scripts and source code is provided by for illustrative purposes only. All examples are untested in different environments and therefore, I cannot guarantee or imply reliability, serviceability, or function of these programs.

All code contained herein is provided to you "AS IS" without any warranties of any kind. The implied warranties of non-infringement, merchantability and fitness for a particular purpose are expressly disclaimed.