It might make you feel better that you are not the only one to have encountered this type of problem. To change the date in your computer, double-click the time which shows in the bottom right of your Taskbar. This will bring up a calendar and clock. No need to change the time, only the date, then press the OK button. Your program will now run for the rest of the day.
Some modern computers get the actual date and time from the Internet.
To be on the safe side, disconnect your phone line from the back of the computer. Don't let your computer figure out that we are in the year 2000. Something happened to my Internet Explorer. The top row of menu items that is immediately below the title bar has disappeared. Previously there was a row of icons above the toolbar that starts with Back and Forward.