Do you mean: ubyte[] ubyte_value = []; dbbind(dbconn, 1, NTBSTRINGBIND, 0, cast(ubyte[])ubyte_value); This error is: test_tds_connect.d(84): Error: function tds.dbbind (tds_dblib_dbprocess* dbproc, int column, int vartype, int varlen, ubyte* varaddr) is not callable using argument types (tds_dblib_dbprocess*, int, int, int, ubyte[])