Not a 100% sure how well XL honors them, but check your Windows
'Regional Settings.'

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Regards,

Tushar Mehta
www.tushar-mehta.com
Excel, PowerPoint, and VBA add-ins, tutorials
Custom MS Office productivity solutions

In article ,
says...
when entering formula in Excel the comma (,) is no longer accepted but the
semicolon (;) now has to be used.
Example:
Previous : =if(a2="Yes",a3+a4,b3+b4)
Now : =if(a2="Yes";a3+a4;b3+b4)

How do I change it back to using commas. I don't know how this has happened,
I just arrived at work one day and the changes has occured.