I am receiving TIMESTAMP value from the iSeries system as an unsigned 64 bit integer value. Is it possible to convert this timestamp into a readable format in windows machine? The iSeries timestamp value is an unsigned 64 bit integer value. All the time management routines which I can use on a windows machine deal with signed integer value. So the iSeries timestamp appears as a negative value to the routines like ctime64() or gmtime64(). Any clues?