XCOPY compares the date provided in the /D switch against the file date to determine which files to copy. In Windows NT, the file date is stored in Universal Time (GMT).
The /D option of the XCOPY command does not specify local time. Instead, XCOPY /D copies all files created GMT 12:00 A.M. or later on the date specified. XCOPY /D: does not convert the entered date from local time to universal time before doing the copy.
For example, if the system is set for PDT (-7) and the following files exist in the Test folder
TEST1.TMP 07/27/98 04:02p TEST2.TMP 07/27/98 05:02p TEST3.TMP 07/28/98 12:01a TEST4.TMP 07/28/98 12:02a
and the following command is entered
the following files are copied:
TEST2.TMP 07/27/98 05:02p TEST3.TMP 07/28/98 12:01a TEST4.TMP 07/28/98 12:02a