I am looking at the collations on the linked server to see if that helps

Here are my configurations:

Oracle 11g

NLS_LANGUAGE = AMERICAN

NLS_TERRITORY = AMERICA

NLS_CHARACTERSET = WE8ISO8859P15

NLS_NCHAR_CHARACTERSET = AL16UTF16

SQL 2008 R2 RTM x64

Linked Server Provider - OraOLEDB.Oracle

Linked Server settings - Collation Compatible = False, Use Remote Collation = True, Collation Name = SQL_Latin1_General_CP1_CI_AS

I have also tried with Collation Compatible = True and no Collation Name

Any help would be great

Thanks