Your pc uses the Turkish language and MerlinXL is not working correctly.
The Turkish character set does not work well with Visual Basic. The problem occurs when converting a word to Upper or Lower case which MerlinXL does to remove case sensitivity.
In particular character sets that do not have a capital letter equivalent, for example i in Turkish or ß in German have problems with MerlinXL
On your desktop, right-click and select Personalise
Change the Regional format to a country other than Turkish ( or German)