The most common cause of this error is incorrect usage of the VIA clause.
USE <.dbf> VIA "<rdd>"
When using the VIA clause with the USE command, always make sure the RDD name is in "quotes" and spelled correctly.
To open a TEST.DBF using the
SIx Driver's SIXCDX flavor, the correct syntax would be:
USE test VIA "SIXCDX"
Another possible cause for this error is attempting to use an RDD that has not been linked into your application. The default RDD (normally DBFNTX, unless SIXCDX.OBJ, SIXNSX.OBJ, SIXMDX.OBJ, or SIXNTX.OBJ have been linked in) is automatically linked into your application. All others must be explicitly declared with the REQUEST command.