Comma showing up instead of a period

[Gahlok]

For some reason whenever I try to use numbers in a cell, instead of
(example)

11.28

it keeps adding a comma, making it

11,28

The system was originally placed in Spanish, but I tried changing it
to english and I'm still having the same issue.

 

[JE McGimpsey]

For some reason whenever I try to use numbers in a cell, instead of
(example)

11.28

it keeps adding a comma, making it

11,28

The system was originally placed in Spanish, but I tried changing it
to english and I'm still having the same issue.

You must quit and restart XL after changing the System preferences to
English - XL reads the prefs when it first starts up.