Commented Unassigned: SUMIF, AVERAGEIF, COUNTIF corrupted worksheet [15225]

Hello!
Hope someone can help me with this. I'm using the 4.0.3 version of the DLL and every time when I add to formula __sumif__, __averageif__ or __countif__ get the warning at opening the excel that there is some unreadable data and Excel can recover the file.

Is anyone also experiencing this?
the formula is like this:
```
ws.Cells["A10"].Formula = "AVERAGEIF("K6:K10";\"<>0\";"K6:K10")";
//or
ws.Cells["A10"].Formula = "SUM("K6:K10")/("4" - COUNTIF("K6:K10";\"0\"))";
```
if I extract the .xlsx and open sheet1.xml this is under the formula for example:
> <f>SUM(K6:K10)/(4 - COUNTIF(K6:K10;"0"))</f>

Any help would be really appreciated!

Cheers
Comments: Hello, I have tried with commas, but I've got the same error as before :( Not sure what I'm doing wrong here. I switched all ; to , in the formulas, but the file gets corrupted again. If I just use AVERAGE or SUM its OK, but if I user SUMIF or AVERAGEIF the file gets corrupted. Can you point me in the right direction what could be wrong? cheers