Copying *.mdf database from machine to another affects logins,

Copying *.mdf database from machine to another affects logins,


I’m wondering why coping the *.mdf to another machine makes it impossible for the users to access their databases.

Scenario:

1. A user B1 is created on the N.mdf database

Attachment 27709

2. B1 is added automatically on the users of the N.mdf and in the logins of the security of the SQL database

Attachment 27710

3. Of course, B1 is able to access the N.mdf database

Attachment 27711

4. The N.mdf is copied to another machine and attached to its databases

5. Now, B1 is not able to access the N.mdf

Attachment 27712


What might be the issue here?
Why the users are not able to access their databases as the database is copied to another machine?
How to preserve the logins as the database is copied to another machine?

Thank you

Best

Jamal

Attached Thumbnails