CDO MAPI versions and files

[James Bott]

Everyone,

I notice several of you have been having trouble with CDO lately. I have a client that also in having an issue after they installed a new mail server. I was reading up on CDO today and came across this page which lists all the versions of CDO and has the files available for download (it is a Microsoft site).

https://support.microsoft.com/en-us/hel ... l-versions

You can tell from the number of versions that there are likely to be more than one version of CDO in any LAN, thus there is a fairly good chance that there may issues.

So, the first thing I would do is check the CDO version and OS one the computers having issues. The CDO files may have slightly different names and may be in different locations. Mine is \windows\system32\CDOSYS.DLL (Windows 10). And my CDOSYS.DLL is version 6.6 which is not on the above referenced page (it was last updated in 2011).

I have found that there is a new authentication protocol called NTLM which is used on newer Microsoft mail servers. So if your client is using a MS mail server, one thing to try is setting this value to 2 as shown.

// 0= none, 1= Basic clear text, 2=NTLM
:Item( "http://schemas.microsoft.com/cdo/configuration/smtpauthenticate" ):Value := 2

One word of warning about sending test emails. This happened to me about a year ago. I was sending lots of test mails when all of a sudden configurations that were working, stopped. I thought I was loosing my mind. Finally, I discovered that I had been marked as a spammer and the mail server was blocking me. I think it was due to the volume of mail and/or I had neglected to make sure the SentFrom and ReplyTo were not exactly the same. Anyway, beware.

Regards,
James

[damianodec]

hi James
I leave CDO because in my lan there are a lot of pc that not work with any version or configuration (pc with Win7 and Win10)

[James Bott]

Damiano,

May I ask what are you using now?

James

[damianodec]

hi James,

Code: Select all  Expand view

  DEFINE MAIL oMail ;
      SUBJECT textSubject ;
      TEXT  MessageText ;
      FROM USER ;
      TO "myCust@dominio.it", ;
                "myBoss@gmail.com" ;   
      RECEIPT

   ACTIVATE MAIL oMail

this is enough now for my app but I hope to arrange my app soon with CDO

[James Bott]

For those having CDO problems I just found a very comprehensive list of errors and instructions for dealing with them.

http://www.ctimls.com/Support/KB/Error% ... _Error.htm

Regards,
James

[James Bott]

Damiano,

What you are using now is the basic simple MAPI. This doesn't have any of the advanced features that CDO has so you will have issues with those servers that require the use of those features. You are lucky that the server your client is using doesn't require any of them.

James

[damianodec]

hi James,
thank you for link and help.
I have to use MAPI because I now have not any others solution.
now I try with your link.