About the problems encountered after changing the cell format to date on Excel

[YWChen]

About the problems encountered after changing the cell format to date in Excel
Every time the data format is changed to the date, it will be displayed as #. This problem can be solved by dividing into columns once, but after re-creating a new file and repeating the same operation, the same problem will still occur.
may I know what is the reason?
How could I solve this problem?

My Office version is Microsoft 365MSO (version 2109 Build 16.0.14430.20154) 32-bit

[#2]

@YWChen Well, Excel stores dates as sequential numbers starting from January 1, 1900. Then number 20211008 formatted as a date refers to a data some 55 thousand years into the future. That's beyond the acceptable limits for Excel, hence ##########.

So, you need to enter the data so that is is recognised as one. On my system I can just type 8oct and it automatically gets translated to 2021-10-08 in a date format. Not sure how that would be in Chinese though.