Before to try, I verified if MSMAPI32.OCX exists on my PC.
MSMAPI32.OCX exists on WINNT/SYSTEM32 with the same version (6.0.81.69).
I did an RegSvr32 MSMAPI32.OCX /u before to do RegSvr32 MSMAPI32.OCX.
Unfortunately, it does not works.

Thanks for your solution.

>>To send mails, I use MAPI.Session for W95 / W98 / NT4 and it works well. With W2000 my program fails on the following command : oSession = CREATEOBJECT("MAPI.Session")
>
>I see the same thing, what if you copy MSMAPI32.OCX from a 9x system into Windows\System and run RegSvr32 on it?