'Tools' > 'Options' > 'Composition' > 'Spelling' tab or 'Menu icon' > 'Options' > 'Options' > 'Composition' > 'Spelling' tab You have a couple of options: If you want spell check to check emails before it sends the email: Select: 'check spelling before sending' uncheck if you do not want this to occur - maybe you prefer the option to check as you type or no auto checking. If you want to use Spell check as you type the email, to alert you potential mistakes: Select; 'Enable spell check as you type' uncheck if you do not want this to occur - maybe you prefer the option to check after composing when sending or no auto checking. If you want to completely disable any spell check which means you would need to manually check prior to sending emails: Uncheck / do not select either of the afore mentioned options. click on 'OK' to save any changes to options.