How to set language for date time formatting in TEXT()

[Geuder]

Hi,

I'm running Excel 2010 English on a Windows 7 - Swedish (not English).

In Excel I have created a sheet full of calculations using the TEXT() function.
Suddenly (perhaps due to Win7 upgrade) my Excel doesnt understand

=TEXT(A1;"yyyy") anymore, it wants the date format in Swedish codes, like:
=TEXT(A1;"åååå").

But all the functions are in still in English (thank God!)


Where do I set what language Excel should use to interpret date/time formatting strings?

Best,

/Geuder