How to Kill all Database Connections

The easiest way to kill all database connections is to set the database to SINGLE User mode;

ALTER DATABASE MyDatabase SET SINGLE_USER WITH ROLLBACK IMMEDIATE

then once finished, change this back to normal;

ALTER DATABASE MyDatabase SET MULTI_USER

The slightly more involved method is to use a scripted method to remove all connections to the DB;

Use Master
Go
Declare @dbname sysname
Set @dbname = 'name of database you want to drop connections from'
Declare @spid int
Select @spid = min(spid) from master.dbo.sysprocesses
where dbid = db_id(@dbname)
While @spid Is Not Null
Begin
Execute ('Kill ' + @spid)
Select @spid = min(spid) from master.dbo.sysprocesses
where dbid = db_id(@dbname) and spid > @spid
End