I'am novice in deployment.

I've developed a little project in VS2005 with a SQLExpress mdf database inside (User istance = true).

It is necessary that the other PC have installed SQLExpress?

Thanks

You should be able to get a re-distributable version from MS, and make that a pre-requisite in your deployment.

I'm very new to this as well, but I know I saw that someplace.

You should be able to get a re-distributable version from MS, and make that a pre-requisite in your deployment.

I'm very new to this as well, but I know I saw that someplace.

Yup, that's right.

On the publish page, click the Prerequisites Button, and make sure the "SQL Express" item is selected. Then, when you publish, setup.exe will install SQL Express if it's not already there.