Restoring SQL Server Database - Master Key Not Opening
The problem is the SMK has changed (since the machine has changed). There's an article explaining it here. Just export and import the SMK -- bearing in mind that any encrypted data in your copied-to system will be unreadable.
MSDN articles:
- Backing up the SMK
- Restoring the SMK
Here is a good article specifically on migrating a database that includes encryption:
http://www.sql-server-performance.com/2009/migrating-databases-checklist-part3/3/
But in short, you need to know the original password in order to move it.
You can backup and restore the key (i.e. replicate as you mention) but you'll need access to the remote server, ability to create backup, or copy of backup with original passwords:
http://msdn.microsoft.com/en-us/library/ff848768.aspx
This forum conversation may also prove useful for insight:
http://www.sqlservercentral.com/Forums/Topic775644-146-1.aspx