Excel changed the dates when I opened the CSV
You opened a CSV, and dates that read one way in the file now read another way on screen.
Why it happens
- A CSV has no types.
- This is why the same file opens differently on two computers in the same office.
- The damage becomes permanent when you save.
What to do now
- Do not double-click a CSV you intend to keep.
- If the file has already been saved through Excel, go back to the original attachment rather than trying to repair the column.
- Open it in a text editor first to see the real characters.
- If you control the sender, ask for ISO dates (2026-08-04).
Next time
A date field reads the whole column before it reads any cell, so a file is interpreted once rather than a row at a time.
Start from the vendor price list template.
Related problems
My SKUs turned into scientific notationA column of product codes, barcodes, or order numbers now reads 1.24E+11.The leading zeros disappeared from my spreadsheetProduct codes, zip codes, or account numbers that started with one or more zeros now start with a digit. 00123 is 123, and 07030 is 7030.The supplier sent the same SKU twiceOne product code appears on more than one row of the same file, sometimes with two different prices.My price column will not add upA column that plainly contains prices sums to zero, or sums to less than it should.