Email.vbs - Monitoring POP3 mail server availability using ActiveXperts Network Monitor
ActiveXperts Network Monitor ships with a powerful set of pre-defined checks. Each individual check has a static number of configuration items. To monitor other items, or to combine monitoring items, you can make use of custom VBScript checks.
Most of the built-in checks have a VBScript equivalent, implemented as a Function in a VBScript (.vbs) file. Out-of-the-box, each VBScript function monitors the same items as the built-in check. Feel free to modify a function. The VBScript check can be customized by editing the VBScript function.
To add a new VBScript-based POP3 monitoring check, do the following:
- On the 'Monitor menu', click 'New Monitoring Check (VBScript)'. The 'VBScript Check' dialog box appears;
- In the 'File selection box', select 'Email.vbs';
- In the 'Function selection box', select 'CheckPop3';
- In the 'Function parameters group box' enter the required parameters. You can also load a working sample first by clicking on the 'Load a sample, click here' link.
To customize the above monitoring check, click on the 'Edit button' next to the 'File selection box'. Notepad will be launched. You can now make changes to the VBScript function(s).

Email.vbs script source code
' /////////////////////////////////////////////////////////////////////////////// ' // ActiveXperts Network Monitor - VBScript based checks ' // © ActiveXperts Software B.V. ' // ' // For more information about ActiveXperts Network Monitor and VBScript, please ' // visit the online ActiveXperts Network Monitor VBScript Guidelines at: ' // https://www.activexperts.com/support/network-monitor/online/vbscript/ ' // ' /////////////////////////////////////////////////////////////////////////////// ' Option Explicit Const retvalUnknown = 1 Dim SYSDATA, SYSEXPLANATION ' Used by Network Monitor, don't change the names ' ////////////////////////////////////////////////////////////////////////////// ' // To test a function outside Network Monitor (e.g. using CSCRIPT from the ' // command line), remove the comment character (') in the following 5 lines: ' Dim bResult ' bResult = CheckSmtp( "smtp.activexperts-labs.com" ) ' WScript.Echo "Return value: [" & bResult & "]" ' WScript.Echo "SYSDATA: [" & SYSDATA & "]" ' WScript.Echo "SYSEXPLANATION: [" & SYSEXPLANATION & "]" ' //////////////////////////////////////////////////////////////////////////////////////// ' ////////////////////////////////////////////////////////////////////////////// Function CheckSmtp( strSmtpServer ) ' Description: ' Establish a telnet session to an SMTP mail server and validate its response ' SMTP servers always reply a '220' message when ready to establish a session ' This function uses the Network Component, an ActiveXperts product. ' Network Component is automatically licensed when ActiveXperts Network Monitor is purchased ' For more information about Network Component, see: www.activexperts.com/network-component ' Parameters: ' 1) strSmtp - Host name or IP address of the mail server ' Usage: ' CheckSmtp( "" ) ' Sample: ' CheckSmtp( "smtp.activexperts-labs.com" ) CheckSmtp = retvalUnknown ' Default return value SYSDATA = "" ' Not used by this function SYSEXPLANATION = "" ' Set initial value CheckSmtp = checkTelnet( strSmtpServer, 25, "", "", "", "220" ) End Function ' ////////////////////////////////////////////////////////////////////////////// Function CheckPop3( strPop3Server ) ' Description: ' Establish a telnet session to a POP3 mail server and validate its response ' POP3 servers always reply a '+OK' message when ready to establish a session ' This function uses the Network Component, an ActiveXperts product. ' Network Component is automatically licensed when ActiveXperts Network Monitor is purchased ' For more information about Network Component, see: www.activexperts.com/network-component ' Parameters: ' 1) strPop3Server - Host name or IP address of the mail server ' Usage: ' CheckPop3( " " ) ' Sample: ' CheckPop3( "pop3.activexperts-labs.com" ) CheckPop3 = retvalUnknown ' Default return value SYSDATA = "" ' Not used by this function SYSEXPLANATION = "" ' Set initial value CheckPop3 = checkTelnet( strPop3Server, 110, "", "", "", "+OK" ) End Function ' ////////////////////////////////////////////////////////////////////////////// Function CheckImap( strImapServer ) ' Description: ' Establish a telnet session to an IMAP mail server and validate its response ' IMAP servers always reply a 'IMAP' message when ready to establish a session ' This function uses the Network Component, an ActiveXperts product. ' Network Component is automatically licensed when ActiveXperts Network Monitor is purchased ' For more information about Network Component, see: www.activexperts.com/network-component ' Parameters: ' 1) strImapServer - Host name or IP address of the mail server ' Usage: ' CheckImap( " " ) ' Sample: ' CheckImap( "imap.activexperts-labs.com" ) CheckImap = retvalUnknown ' Default return value SYSDATA = "" ' Not used by this function SYSEXPLANATION = "" ' Set initial value CheckImap = checkTelnet( strImapServer, 143, "", "", "", "IMAP" ) End Function ' ////////////////////////////////////////////////////////////////////////////// ' // ' // Private Functions ' // NOTE: Private functions are used by the above functions, and will not ' // be called directly by the ActiveXperts Network Monitor Service. ' // Private function names start with a lower case character and will ' // not be listed in the Network Monitor's function browser. ' // ' ////////////////////////////////////////////////////////////////////////////// ' ////////////////////////////////////////////////////////////////////////////// Function checkTelnet( strServer, numPort, strCommand1, strCommand2, strCommand3, strReceive ) Dim objTcp, strAllResponses checkTelnet = 1 ' Default return value SYSDATA = "" ' Not used by this function SYSEXPLANATION = "" ' Set initial value Set objTcp = CreateObject("ActiveXperts.Tcp") objTcp.Protocol = 2 ' 1 means: raw, 2 means: telnet (see also Network Component manual) objTcp.Connect strServer, numPort If( objTcp.LastError <> 0 Or objTcp.ConnectionState <> 3 ) Then checkTelnet = False SYSEXPLANATION = "Unable to connect to [" & strServer & "]" objTcp.Disconnect ' can be called even when there's no connection Exit Function End If objTcp.Sleep( 2000 ) ' Allow some time tcprecv objTcp, strAllResponses tcpsend objTcp, strCommand1 tcprecv objTcp, strAllResponses tcpsend objTcp, strCommand2 tcprecv objTcp, strAllResponses tcpsend objTcp, strCommand3 tcprecv objTcp, strAllResponses If( InStr( UCase( strAllResponses ), UCase( strReceive ) ) <> 0 ) Then checkTelnet = True Else checkTelnet = False End If SYSEXPLANATION = "Response=[" & strAllResponses & "]" objTcp.Disconnect End Function ' ////////////////////////////////////////////////////////////////////////////// Sub tcpsend( objTcp, strCommand ) If( strCommand <> "" ) Then objTcp.SendString( strCommand ) End If End Sub ' ////////////////////////////////////////////////////////////////////////////// Sub tcprecv( objTcp, BYREF strAllResponses ) Dim bHasData, strResponse bHasData = objTcp.HasData While( bHasData ) strResponse = objTcp.ReceiveString() bHasData = objTcp.HasData If( strAllResponses <> "" ) Then strAllResponses = strAllResponses & ".." ' .. to indicate a newline End If strAllResponses = strAllResponses & strResponse WEnd End Sub