It could be a cultural thing, see: c# 4.0 - how to set default culture info for entire c# application - Stack Overflow
As you probably are using a German Windows version, comma's are expected for the decimals.
It could also be that you have comma's for the decimals in your text file, the Split(',')
will then truncate them.
It would be better to use ';' as a separator (or TAB if you prefer that) and then use Split(';')