In Debwin, output similar to the following is found:
... ->LsMailSendFile(0X01EA3F50,0x003904fa) ->MAPI init ->MAPI present: WIN.INI=0 ->MAPI present: registry=0 -><MAPI init ->clsMAPI::Send(mode=0) ->EXCEPTION(MAPI is not installed or cannot be used) ->clsMAPI::Logoff -><clsMAPI::Logoff failed: MAPI not ready ->Error: MAPI is not installed or cannot be used >=-1016 (LL_ERR_STG_UNEXPECTED) ...
The reason is that the e-mail client installed on this system doesn’t support SimpleMAPI or that its installation hasn’t fully “configured” MAPI.
List & Label checks the entry ‘MAPI’ in the section ‘[Mail]’ in the file ‘win.ini’ (to be found in the “Windows” folder). It should be set to “1”.
Additionally, in the registry the string ‘MAPI’ is checked for value “1” under ‘HKEY_LOCAL_MACHINE\Software\Microsoft\Windows Messaging Subsystem’. Please note that on a 64-Bit system the corresponding “correct” sub key is checked. If your application is a 32-Bit process the corresponding key is ‘HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Windows Messaging Subsystem’. A 64-Bit application however searches its settings under ‘HKEY_LOCAL_MACHINE\Software\Microsoft\Windows Messaging Subsystem’.
If none of these two checks was successful List & Label assumes that SimpleMAPI cannot be used as MAPI is not installed (these entries are official defaults from Microsoft). Please also note the hints in the Programmer’s Reference under “Send Export Results via E-Mail” as well as the export option “Export.Mail.Provider”.
Further information can be found under the following link.