PU12 - No data for Export file

I ran PU12 Export function using interface 'OTMU' with one employee; the log showed one record selected with appropriate infotype information; but there is no data exported. I tried with a custom Interface file for IT0002 and It0008 with the same employee; same result ( no data exported).

Your assistance is much appreciated (ECC 5.0, WAS 6.40)

Thanks

Vince