but can u tell me , how can i get data from an MDE file, when i make changes to the database by original MDB file.
IF you make a design change to the database (ie. form, add a query, etc...) you must re-create the MDE/ACCDE file.
There is no way to reverse the process; thus, the requirement to keep a working copy of the MDB/ACCDB file.
i want to know the backup process from MDE file & restore process.
You do not go back from an MDE to a MDB. Keep a copy of the MDB file for development.
i have another problem, that is if i give the MDE file to a user, he can easily copy it and give it to others. How can i prevent this from happening
Normally, new question, new thread; however, this one is a short answer: You can not easily prevent this from happening.
There is nothing you can do that a smart user can not bypass in Access other than the MDB/ACCDB to MDE/ACCDE conversion (and even then, there are hex editors and some very savy blackhats that more than likely can still reverse engineer the application)
IF you want more ideas - new thread please.