Note that some Windows 2003 systems might require modification to the ADD_XP.SQL installation script.  The following is a script change that might need to be made for some Windows 2003 systems.

Change:

EXEC sp_addextendedproc xp_nysiis, 'xp_nysiis.dll'

GO

EXEC sp_addextendedproc xp_levenshtein, 'xp_levenshtein.dll'

To:

EXEC sp_addextendedproc xp_nysiis, 'C:\Program Files\Microsoft SQL Server\MSSQL\BINN\xp_nysiis.dll'

GO

EXEC sp_addextendedproc xp_levenshtein, 'C:\Program Files\Microsoft SQL Server\MSSQL\BINN\xp_levenshtein.dll'

The directory used above is the default directory for C: drive installations.  Replace the directory with your appropriate SQL Server directory in the lines above, as necessary.

Also, it may be necessary to download the two Microsoft redistributable DLL files and copy them to your MSSQL\BINN directory on some Windows 2003 systems.  These files are OPENDS60.DLL and MSVCR71.DLL.  They can be downloaded as part of the SQL Encryption Toolkit here.