A spell check is possible for text fields and text documents (letters, data sheets). You can set which dictionary is used as the basis for the check at  Aministration >  Settings >  Company >  Settings > Languages > Dictionary .

1. An automatic spell check is activated by default for all text fields, but can be deactivated via the tab in the function bar  Options >  Settings . If the cursor is positioned in a text field, all words that are not in the dictionary are marked with a red dotted line during automatic checking. A manual spell check is also possible if the automatic check has been deactivated.
2. To do this, open the text document (letter, email) you want to check and place the cursor in the document or text field by left-clicking.
   Note: Spell checking is not possible in the preview or in the HTML view.
3. Press F7 or click on  Spell check.
4. Alternatively, right-click on the desired word and select  Spelling.
5. The words that are not in the linked dictionary are displayed one after the other in the dialogue window.
   1. If the word is correct, click on Learnto add the word to the dictionary.
   2. If the word is wrong, double-click to select one of the suggested corrections or enter your own and click Change or Always replace.
6.  Save your input by clicking on the icon in the top left-hand corner of the input window