I don't really use this forum and the forum link for DBD::ODBC points to the dbi-users mailing list. However, I've no explanation for the undefined references you are getting with iODBC unless iODBC has not exported those symbols so I'd check how iODBC was built. May be try a nm -a (or whatever cygwin uses) to check the iodbc library and see what symbols it exports. Normally people use unixODBC, not iODBC but on cygwin I thought the default was to build against the MS ODBC driver manager. Sorry I cannot be more helpful. I neither use cygwin or iodbc. Perhaps you'll have better luck on the dbi-users mailing list or on irc.perl.org in the #dbi channel. BTW, the combination of DBD::ODBC and iODBC will not do unicode properly at all - see the unicode section in the DBD::ODBC docs.