Hello,

I have to create 400 home folders, and i need when the user open his home folder a message appear " This folder is temporary" how it can be done.

I don't think there is a way to easily trigger any sort of message by simply opening a folder.  However, you can create a logon script that displays a message to the user each time the user logs in.  The message could include the folder name with the comment that it is temporary.