[ODBC Driver Manager] The Specified DSN contains an architecture mismatch between the Driver and Application

Hi,
I am having a problem with an OSQL command. The command is to backup a database. It is the same command I used when the database was on XP 32-bit. The database is now on Windows Server 2008 64 bit.
The command is:
OSQL -E -n -D WhatsUp -Q "BACKUP DATABASE WhatsUp TO DISK ='C:\WhatsUp.bak' WITH INIT"
The result is:
[ODBC Driver Manager] The Specified DSN contains an architecture mismatch between the Driver and Application.

Could anyone point me in the direction?
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