Creating email in outlook

[John]

Hi

I am trying to find the way to create an email in outlook. I am using the
code given at the end. It works fine the first time but calling the code
second time gives the following error;

Unhandled Exception: System.Reflecti on.TargetInvoca tionException: Exception
has been thrown by the target of an invocation. --->
System.Runtime. InteropServices .InvalidComObje ctException: COM object that
has been separated from its underlying RCW can not be used.
at Outlook.Applica tionEvents_Even tProvider..ctor (Object )

The error comes on the 'OutlookApp = New Outlook.Applica tion' line. Any
ideas what I am missing?

Thanks

Regards

= Code Follows =============== ========

Imports System.Runtime. InteropServices

Public Class clsOfficeWrappe r
Private WithEvents OutlookApp As Outlook.Applica tion
Private WithEvents em As Outlook.MailIte m

Public Sub NewEmail(ByVal EmailTemplate As String, ByVal SendTo As String)
Dim ns As Outlook.NameSpa ce

OutlookApp = New Outlook.Applica tion ' <=== This lines give the
exception second time round
ns = OutlookApp.GetN amespace("MAPI" )
ns.Logon()

em = DirectCast(Outl ookApp.CreateIt emFromTemplate( EmailTemplate),
Outlook.MailIte m)
.To = SendTo
.Display(False)

Marshal.Release ComObject(em)
ns.Logoff()
Marshal.Release ComObject(ns)
Marshal.Release ComObject(Outlo okApp)
End Sub
....

End Class

[Jay B. Harlow [MVP - Outlook]]

John,

Marshal.Release ComObject(Outlo okApp)
Do not use ReleaseComObjec t if you are using WithEvents! ReleaseComObjec t
will release the com object, which means the com object itself is no longer
valid. WithEvents will try to remove the event handlers on the previous
object (the one you just destroyed) when you create a new instance of it.
The previous object is a .NET object, that had its com object destroyed,
WithEvents is not able to remove the COM event handlers, hence the
exception!
Public Class clsOfficeWrappe r
Private WithEvents OutlookApp As Outlook.Applica tion
Private WithEvents em As Outlook.MailIte m
Seeing as OutlookApp & em are class level variables you should create them
in the class's constructor (Sub New) and destroy them (ReleaseComObje ct)
using the Disposable/Finalization pattern.

For info on implementing Dispose along with Finalize (you really should
implement both!) see:

http://msdn.microsoft.com/library/de...izeDispose.asp

If you truly need to handle the events in the NewEmail method I would
suggest you use AddHandler & RemoveHandler and move the variables local to
the Subroutine.
Public Sub NewEmail(ByVal EmailTemplate As String, ByVal SendTo As String) Dim OutlookApp As Outlook.Applica tion
AddHandler OutlookApp...
Dim em As Outlook.MailIte m
AddHandler em... Dim ns As Outlook.NameSpa ce

OutlookApp = New Outlook.Applica tion ' <=== This lines give the
exception second time round
ns = OutlookApp.GetN amespace("MAPI" )
ns.Logon()

em = DirectCast(Outl ookApp.CreateIt emFromTemplate( EmailTemplate),
Outlook.MailIte m)
.To = SendTo
.Display(False)
RemoveHandler em... Marshal.Release ComObject(em)
ns.Logoff()
Marshal.Release ComObject(ns) RemoveHandler OutlookApp... Marshal.Release ComObject(Outlo okApp)
End Sub
Of course if you are not handling any events then the AddHandler &
RemoveHandler are not needed...

Hope this helps
Jay

"John" <jo**@nospam.in fovis.co.uk> wrote in message
news:O%******** ********@TK2MSF TNGP10.phx.gbl. .. Hi

I am trying to find the way to create an email in outlook. I am using the
code given at the end. It works fine the first time but calling the code
second time gives the following error;

Unhandled Exception: System.Reflecti on.TargetInvoca tionException: Exception has been thrown by the target of an invocation. --->
System.Runtime. InteropServices .InvalidComObje ctException: COM object that
has been separated from its underlying RCW can not be used.
at Outlook.Applica tionEvents_Even tProvider..ctor (Object )

The error comes on the 'OutlookApp = New Outlook.Applica tion' line. Any
ideas what I am missing?

Thanks

Regards

= Code Follows =============== ========

Imports System.Runtime. InteropServices

Public Class clsOfficeWrappe r
Private WithEvents OutlookApp As Outlook.Applica tion
Private WithEvents em As Outlook.MailIte m

Public Sub NewEmail(ByVal EmailTemplate As String, ByVal SendTo As String)
Dim ns As Outlook.NameSpa ce

OutlookApp = New Outlook.Applica tion ' <=== This lines give the
exception second time round
ns = OutlookApp.GetN amespace("MAPI" )
ns.Logon()

em = DirectCast(Outl ookApp.CreateIt emFromTemplate( EmailTemplate),
Outlook.MailIte m)
.To = SendTo
.Display(False)

Marshal.Release ComObject(em)
ns.Logoff()
Marshal.Release ComObject(ns)
Marshal.Release ComObject(Outlo okApp)
End Sub
...

End Class

[John]

Thanks. Great. That has worked nicely.

Regards
"Jay B. Harlow [MVP - Outlook]" <Ja************ @msn.com> wrote in message
news:uu******** ******@TK2MSFTN GP11.phx.gbl...

John,

Marshal.Release ComObject(Outlo okApp)
Do not use ReleaseComObjec t if you are using WithEvents! ReleaseComObjec t
will release the com object, which means the com object itself is no

longer valid. WithEvents will try to remove the event handlers on the previous
object (the one you just destroyed) when you create a new instance of it.
The previous object is a .NET object, that had its com object destroyed,
WithEvents is not able to remove the COM event handlers, hence the
exception!

Public Class clsOfficeWrappe r
Private WithEvents OutlookApp As Outlook.Applica tion
Private WithEvents em As Outlook.MailIte m
Seeing as OutlookApp & em are class level variables you should create them
in the class's constructor (Sub New) and destroy them (ReleaseComObje ct)
using the Disposable/Finalization pattern.

For info on implementing Dispose along with Finalize (you really should
implement both!) see:

http://msdn.microsoft.com/library/de...izeDispose.asp
If you truly need to handle the events in the NewEmail method I would
suggest you use AddHandler & RemoveHandler and move the variables local to
the Subroutine.

Public Sub NewEmail(ByVal EmailTemplate As String, ByVal SendTo As String)

Dim OutlookApp As Outlook.Applica tion
AddHandler OutlookApp...
Dim em As Outlook.MailIte m
AddHandler em...

Dim ns As Outlook.NameSpa ce

OutlookApp = New Outlook.Applica tion ' <=== This lines give the
exception second time round
ns = OutlookApp.GetN amespace("MAPI" )
ns.Logon()

em = DirectCast(Outl ookApp.CreateIt emFromTemplate( EmailTemplate),
Outlook.MailIte m)
.To = SendTo
.Display(False)

RemoveHandler em...

Marshal.Release ComObject(em)
ns.Logoff()
Marshal.Release ComObject(ns)

RemoveHandler OutlookApp...

Marshal.Release ComObject(Outlo okApp)
End Sub

Of course if you are not handling any events then the AddHandler &
RemoveHandler are not needed...

Hope this helps
Jay

"John" <jo**@nospam.in fovis.co.uk> wrote in message
news:O%******** ********@TK2MSF TNGP10.phx.gbl. ..

Hi

I am trying to find the way to create an email in outlook. I am using

the code given at the end. It works fine the first time but calling the code
second time gives the following error;

Unhandled Exception: System.Reflecti on.TargetInvoca tionException:

Exception

has been thrown by the target of an invocation. --->
System.Runtime. InteropServices .InvalidComObje ctException: COM object that has been separated from its underlying RCW can not be used.
at Outlook.Applica tionEvents_Even tProvider..ctor (Object )

The error comes on the 'OutlookApp = New Outlook.Applica tion' line. Any
ideas what I am missing?

Thanks

Regards

= Code Follows =============== ========

Imports System.Runtime. InteropServices

Public Class clsOfficeWrappe r
Private WithEvents OutlookApp As Outlook.Applica tion
Private WithEvents em As Outlook.MailIte m

Public Sub NewEmail(ByVal EmailTemplate As String, ByVal SendTo As String) Dim ns As Outlook.NameSpa ce

OutlookApp = New Outlook.Applica tion ' <=== This lines give the
exception second time round
ns = OutlookApp.GetN amespace("MAPI" )
ns.Logon()

em = DirectCast(Outl ookApp.CreateIt emFromTemplate( EmailTemplate),
Outlook.MailIte m)
.To = SendTo
.Display(False)

Marshal.Release ComObject(em)
ns.Logoff()
Marshal.Release ComObject(ns)
Marshal.Release ComObject(Outlo okApp)
End Sub
...

End Class