why would you want to do this? its a headache waiting to happen and is not even worth trying due to issues with passwords in the long run, if the reason is to share a mail box create a mail in database and give both of the users access, then they can keep their email boxes separate and work as a group on the shared box.

But i have install 1.same id in both the system
2.and share the archive of the one system.so one will do the archive of the mail i did
3.but the other system also need to do archive? without this is need to do
4. can u give me steps for this installation if it is possible

Thanks 4r information

but still i am new for this lotus notes client side

you dont need to share the id file for an archive unless the archive is encrypted or there is an ACL set, typically you can choose these options when creating the archive

if encryption is your concern, just click the do not locally encrypt found in encryption settings..