Did you perfrom a full backup or a log backup with the truncate_only optionprior to running teh shrinkfile command?

Backup the database or truncate the transaction log. Run the following statements.

DBCC SHRINKFILE ('<logical file name>', EMPTYFILE )

ALTER DATABASE <Database name>  REMOVE FILE <logical file name>

Do a full backup...

Try running sp_spaceused with the updateusage parameter set to TRUE. It may run for along time but should correct the size inconsistencies you see.

EXEC sp_spaceused @objname = 'TableName', @updateusage =...

Have you restarted the SQL Service since running sp_dropserver and sp_addserver?

1) Make sure all the referenced tables are indexed on columns used in joins or in the where clause of the sub-queries. Updating statistics won't help if appropriate indexes don't...