DATE and TIME are MS-DOS-commands. It's remarkable you quote them in relation to Windows.
If somehow the Windows software regarding date and time is corrupted, try the DOS-equivalent. Just open a command window, type date (enter) and enter the new date. Same with time. Then exit.
If it doesn't work in a command window, then boot into MS-DOS (it's a choice in the Start>Shutdown screen). Then after changing date and time type win in stead of exit.
If any of the above works, and you've got no other problems, I think you should accept this minor annoyance.
Unable to change date or time in Windows 98. My PC freezes when I try to change the time or date. My computer has not changed since the change from daylight savings time Pacific Coast time.
Does the date and time command use a WINdows (specific driver).