This is a common issue that can creep up on you when using SQL Server.  More than likely, you either uninstalled SQL Server or manually detached the StrataFrameSample database.  However, neither of these will delete the mdf and ldf files.  So when you then turn back around and try to install, it will attempt to create those files but they already exist on disk and thus the error.  To get around this, make sure that the StrataFrameSample database is not attached to your SQL Server, and then go to the c:\program files\microsoft sql server\... (wherever you install SQL Server) and go to the data directory and manually delete the StrataFrameSample.mdf and StrataFrameSample.ldf files...then try again

I get an error when installing Strataframe.

Here is the log file:

• 1/19/2008 10:11:57 AM -> Deploying meta-data for database 'StrataFrameSample'
X 1/19/2008 10:11:58 AM -> Creating database 'StrataFrameSample' failed.FailedOperationException
  Create failed for Database 'StrataFrameSample'.
ExecutionFailureException
  An exception occurred while executing a Transact-SQL statement or batch.
SqlException
  CREATE DATABASE failed. Some file names listed could not be created. Check related errors.
Cannot create file 'C:\Program Files\Microsoft SQL Server\MSSQL.1\MSSQL\DATA\StrataFrameSample_log.LDF' because it already exists. Change the file path or the file name, and retry the operation.

Source     : Microsoft.SqlServer.Smo

Stack Trace:
   at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection)
   at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection)
   at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj)
   at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj)
   at System.Data.SqlClient.SqlCommand.RunExecuteNonQueryTds(String methodName, Boolean async)
   at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(DbAsyncResult result, String methodName, Boolean sendToPipe)
   at System.Data.SqlClient.SqlCommand.ExecuteNonQuery()
   at Microsoft.SqlServer.Management.Common.ServerConnection.ExecuteNonQuery(String sqlCommand, ExecutionTypes executionType)
   at Microsoft.SqlServer.Management.Common.ServerConnection.ExecuteNonQuery(StringCollection sqlCommands, ExecutionTypes executionType)
   at Microsoft.SqlServer.Management.Smo.ExecutionManager.ExecuteNonQuery(StringCollection queries)
   at Microsoft.SqlServer.Management.Smo.SqlSmoObject.ExecuteNonQuery(StringCollection queries, Boolean includeDbContext)
   at Microsoft.SqlServer.Management.Smo.SqlSmoObject.CreateImplFinish(StringCollection createQuery, ScriptingOptions so)
   at Microsoft.SqlServer.Management.Smo.SqlSmoObject.CreateImpl()
   at Microsoft.SqlServer.Management.Smo.Database.Create()
   at MicroFour.StrataFrame.DBEngine.SQL.DatabaseMigrator.CreateSmoObject(ICreatable ObjectToCreate, String ObjectName, DBEObjectType ObjectType)

• 1/19/2008 10:11:58 AM -> Finished verifying databases on server.
• 1/19/2008 10:11:58 AM -> The meta data conversion to the SQL Server has been completed.
X 1/19/2008 10:11:58 AM -> An error occurred while deploying the data to the server.NullReferenceException
  Object reference not set to an instance of an object.

Source     : MicroFour StrataFrame DBEngine

Stack Trace:
   at MicroFour.StrataFrame.DBEngine.SQL.DatabaseMigrator.TurnOffAllForeignKeys(String DatabaseName)
   at MicroFour.StrataFrame.DBEngine.SQL.DatabaseMigrator.DeployDataThread()