"Warning: no valid values" using Synthesize

[Frank Fineis]

I've been using R to write .txt files to the datasets/datain directory, and from there proceeding through the normal steps to create synthetic datasets.

Upon hitting "synthesize," the job immediately fails with a log file with the following warnings:

Warning: No valid values for StudentGender13

           Type changed to transfer

Warning: No valid values for ReadingLevel13

           Type changed to transfer

Warning: No valid values for Race13

           Type changed to transfer

...(more warnings for ~8 other categorical variables)

And then failure was due to "Error: Imputation too big - possibly continuous variable specified as categorical," which is understandable I suppose given I have two categorical variables with ~1000 different levels.

My main concern is regarding the warning. I've tried importing data as both quoted and then unquoted; is this easily diagnosed?

Thank you,

Frank