=ROUNDUP(D456*1.25,0) message reads " The formula you typed contains an error"
highlighted is 1.25,0.
I took this file to another machine and it worked fine.... not sure what went wrong, but will try and address a reinstall of Excel
reinstallation should be unnecessary. It should be done only as a last resort.
Did you try my suggestion about using semicolon instead of comma for the parameter separator.
The problem might simply be the regional configuration (control panel) on the computer. Or if you use office 365, however the "cloud" version determines regional differences.
(i don't know anything about office 365. I avoid it like the plague.)