Excel: NOW Returns #NUM! or TODAY Returns an Incorrect Result

SUMMARY

The NOW function returns the #NUM! error and the TODAY function produces incorrect results in Microsoft Excel if your computer's built-in clock is set to a date outside Excel's date range of January 1, 1900 to December 31, 2078.

MORE INFORMATION

The NOW function returns the serial number of the current date and time and the TODAY function returns the serial number of the current date. The "current" date and time are determined by your computer's built-in clock. If you receive the #NUM! error when using the NOW function, or the TODAY function returns an incorrect serial number, change your computer's internal clock to an appropriate date within the limits of Microsoft Excel's date range.

If you are using Windows 3.0, it is necessary to set the date at the MS-DOS level. In the Windows 3.0 Control Panel, the Date/Time setting only displays the last two digits of a given year. It is therefore possible that the Control Panel's clock displays a date that appears correct but is actually set to the wrong century.

Note that the TODAY function is only available in Excel version 3.0.

REFERENCES

"Microsoft Excel Function Reference," version 3.0, pages 161, 237

"Microsoft Excel User's Guide," version 3.0, page 95