I have run into a really weird problem with Excel recently. For some reason, when data from certain spreadsheets is copied and pasted into another workbook, the dates displayed in the copied data shift by four years and one day into the past. The numeric value storing the date is not changing, just what date is displayed. I have been able to reproduce the error just through copy and paste actions, and it appears to be a general problem, not just on my computer. Has anybody else encountered this problem? I'm running Excel XP, but it is at least possible that the folks doing data entry are running Excel 2000.