Do the following :
Actions===> Archive ===Settings
Set the Location where you want to have the Archive file to be created ……
Select all the message to need to get red of , move from the Mailbox and have some more space …. ….. Select ” Archive Selected Documents”
The Above mentioned steps are the ones to be applied on Lotus Notes Client not the
the only way is to archive by creating a n Archiving Policy on the server and set a server side Archiving .