Protect Access program

With Access, you cannot generate a standalone EXE.

You can distribute your database with a password on the VBA project to protect the source code.   In addition, you can also distribute as a "compiled" app, which is a MDE.  This is a DB with the source code stripped out.

Even with all that however, someone who is very determined could still figure out your code.

To help with that, you could use:

http://www.everythingaccess.com/mdeprotector.htm

In terms of registering/securing your app from a licensing standpoint, there is this:

http://www.peterssoftware.com/ka.htm

Jim.

And there is user authentication.
How to control the number of user?
I want only 2 users to be logged in at a time.

You'd have to control that yourself. Essentially, you'd have to log users when they connect, and log them out when they disconnect. This can be tough to do, especially if you have users who are in the habit of using the power button on their machine to log out.

What's the reason for having only 2 users? If this has to do with licensing, then I'd suggest something like what JimD suggest, or this: http://www.ssware.com/cryptolicensing/cryptolicensing_ocx.htm. This is an industrial strength library that will do what you need. I use it for my .NET projects, but I've used the ActiveX version as well.

I have user authentication.
But not sure how to control that. I have a table to store username and password.

Not sure how to control what?

If you only want two users in the database, then when User1 logs in you would write a record somewhere (perhaps you'd have a Logins table). When User2 logs in, you check the Logins table to see the number logged in. If it's less than 2, you allow User2 to log in.

When User1 logs out, you either remove that record from the Logins table, or you "close" it (i.e. stamp it with the logout date/time).

The trouble comes when User1 doesn't log out, but instead uses the power button on the machine to close it out, or when the network drops, or any of a dozen other scenarios. When these happen, the Logins table is not updated, and the system will consider User1 to still be logged in.

So back to my comment:

What's the reason for having only 2 users

If you can let us know why you only want two users logged in, we might be able to provide you with better suggestions.

I started with 2 users. Now they are telling me to give them a user with admin permission to create another user so only 2 users can login at the same time.
Note: I told them you can keep only upto 4 active users.

The comments that Scott and I posted at the start contain everything you need to protect your app and control the number of users.

Note that were assuming that you telling them they can only have 4 users is a restriction you want and not a problem with the app.

 A well written Access app can handle 30 to 40 users without issue and if a SQL server backend, more than that.

Jim.

One more thing I have seen one of my friend did this. He just run the exe automaically a shortcut created on desktop and db copued to c drive. I think he just coped the shortcut and and copied the db and created as a package in VS2010.
I am not sure of how he did that or he got it from somewhere else.
Any idea of how it will be?

With Access, you cannot create a standalone .exe

Either the Access run time or the full Retail version must be installed in order to use the DB (they are in fact one in the same, it's just some registry keys that controls the "mode" your allowed to use it in).

I would assume what your friend did is created an install package that included the run time version of Access along with the DB.

Jim.

Yes you are right I saw first it installed runtime and copied the DB.

How to do the same?

Thanks