Se você estiver usando o MS Word também, ele pode estar sendo usado para compor seus e-mails no Outlook.
Nesse caso, verifique se a opção Verificar ortografia ao digitar está ativada no Word e desative a Verificação ortográfica em Enviar no Outlook.
De aqui :
To set Word as the default editor for email messages in Outlook:
- Select Tools->Options from the menu in Outlook.
- Click on the Mail Format tab.
- Make sure the Use Microsoft Office Word 2003 to edit e-mail messages checkbox is selected.
- In versions before Outlook 2003, the text
Do documento KB kobaltz vinculado ( KB937422 ):
Word 2003, Word 2002, and Word 2000
- On the Tools menu, click Options, and then click the Spelling & Grammar tab.
- Click to clear the Check spelling as you type check box.
- Click to clear the Check grammar as you type check box.
Important The Check spelling as you type and Check grammar as you type
settings will affect any open documents in Word. If other people use
the documents, you may want to notify the people that you made this
change.