Why isn't spellcheck working in Outlook and how to fix it

Enable automatic spellcheck

The first thing to check is whether Outlook is set to detect spelling and grammar errors while you compose emails.

1. In Outlook, go to File > Options > Mail.
2. Under Compose messages section, click either Editor options or Spelling and Autocorrect (both open the same dialog window).
3. In the Editor Options window, select Proofing from the left menu.
4. Under When correcting spelling in Outlook, make sure these options are turned on:
   • Check spelling as you type – automatically detect and highlight misspelled words as you compose an email.
   • Mark grammar errors as you type – flag grammatical mistakes in your text.
   • Frequently confused words – detect words that are spelled correctly but may be used incorrectly in context, for example "their" instead of "there".
5. Click OK to save the changes.

With these options enabled, Outlook should underline all misspelled words in your emails in red.

Enable spelling check before sending emails

If you want Outlook to check your emails for spelling mistakes and alert you to any errors before sending, you can enable an additional proofreading option:

1. Go to File > Options > Mail.
2. Under Compose messages, select Always check spelling before sending and click OK.

Think of it as an extra safeguard, even when automatic spellcheck is enabled. After all, it's easy to overlook mistakes underlined while you're typing, and this final check gives you another chance to catch them before your message reaches the recipient.

Check the default language and install proofing tools

If spell check isn't working correctly in classic Outlook, the wrong default language or missing proofing tools may be the cause. Even regional variations matter: for example, British and American English spell certain words differently (colour vs. color).

To check your language settings in Outlook:

1. Go to File > Options > Language.
2. Under Office authoring languages and proofing, check which language is marked as <preferred>.
3. If your main language isn't at the top of the list, select it and click Set as Preferred.
4. Check the proofing status next to the language. If it says Proofing available, click the link to install the missing proofing tools. If it says Proofing installed, everything is ready.
5. Add a missing language. If the language you need isn't listed, click Add a Language, select the desired language, and click Add.
6. Click OK to save your changes.
7. Restart Outlook for your new language settings to take effect.

Review spelling exceptions and custom dictionaries

Sometimes Outlook checks spelling correctly but deliberately ignores certain words. To review the relevant options:

1. Go to File > Options > Mail > Spelling and Autocorrect > Proofing.
2. Under When correcting spelling in Microsoft Office programs, clear any options that prevent Outlook from detecting mistakes you want to catch such as:
   • Ignore words in UPPERCASE
   • Ignore words that contain numbers

   For example, if Ignore words in UPPERCASE is enabled, Outlook may skip a misspelled word written entirely in capital letters.

3. If the problem affects only a particular word, click Custom Dictionaries in the same section and review the entries in your dictionary. Remove any misspelled words that were accidentally added.

Note that these changes will affect spellchecking across all Microsoft Office applications, not just Outlook.

Choose the correct proofing language for a message

Outlook may not recognize spelling mistakes if your message or its specific part is assigned the wrong proofing language. For example, an English email might be checked against a French dictionary.

Select the affected text and make sure the correct language is used for proofreading:

1. Click anywhere in the message body and press Ctrl + A to select all the text. If a particular part of your message is in a different language and isn't being checked correctly, select only that part.
2. On the Review tab, click Language > Set Proofing Language.
3. In the dialog box that opens, select the language you're writing in.
4. Make sure Do not check spelling or grammar is unchecked.
5. If you want Outlook to use this language for future messages, click Set As Default and confirm by clicking Yes.
6. Back in the main Language dialog box, click OK to apply the updated settings.

Run spellcheck manually

If automatic checking still doesn't highlight errors, try launching it manually. This will help determine whether the problem affects the entire Outlook spelling checker or just the automatic detection feature in a particular email.

1. In the email you are composing, go to the Review tab > Proofing group > Spelling & Grammar or press F7.
2. Depending on your Outlook version:
   • In classic Outlook 365, Microsoft Editor opens a pane with spelling, grammar, and writing suggestions.
   • In Outlook 2024 – 2010, the traditional Spelling and Grammar dialog guides you through mistakes one at a time.

If manual checking detects errors but automatic checking doesn't, revisit the Automatic spellcheck settings.

Check Microsoft Editor settings

Microsoft Editor lets you control the spellchecker settings as well as the languages used for proofreading. If these settings are incorrect, Outlook may miss spelling mistakes or stop showing suggestions altogether.

To check and adjust Editor settings:

1. On the Message tab, click the three-dot menu and select Editor > Editor Settings.
2. In the Microsoft Editor Settings pane, review the following:
   • Spelling and grammar corrections. Make sure the Spelling and Grammar categories are enabled so Editor can detect and highlight errors.
   • Proofing language. Check that the selected language matches the language you're writing in. If your preferred language is missing, click Manage spellcheck languages to add it.
   • Other writing suggestions. Review the available refinement options and enable those you want Editor to check, such as clarity, conciseness, or formality.
3. If you're unsure which settings have been changed, click Reset to default to restore the original configuration.
4. Click OK to apply the settings.

After updating the settings, type a few deliberately misspelled words in a new email to see whether Editor detects them.

Open the message in a separate window

If spell check isn't working when you compose a new email inline or reply directly in the Reading pane, try opening the message in a separate window. Click Pop-out to a new window to force Editor to load properly. If spell checking works in the separate window, you can finish composing and send your reply from there.

Check your internet connection and browser

New Outlook and the web versions of Outlook rely on online services for some Microsoft Editor functionality. Connection problems or browser-related issues may interfere with suggestions.

Try these simple fixes:

1. Check that your internet connection is stable.
2. Refresh Outlook on the web or close and reopen new Outlook.
3. If you're using Outlook in a browser, try opening it in a private window.
4. Temporarily disable browser extensions that modify text or provide spelling and grammar corrections.
5. Update your browser to the latest version.

If spellcheck functions correctly in a private browsing window but not in your regular browser session, a browser extension or stored website data may be responsible.

Change the email format to HTML

If Outlook isn't highlighting spelling or grammar errors in a specific email, check the message format. Automated Outlook proofing occasionally pauses if an email is set to Plain text. Try switching to HTML to see if that resolves the issue.

After changing the format, type a misspelled word to check whether Outlook detects it.

Note. Plain text formatting does not normally disable spell checking. If changing to HTML doesn't help, the problem is likely related to your proofing settings or another issue.

Check Windows spelling settings

Windows has its own spelling settings that may affect highlighting typing errors in certain applications. To check them:

1. Open Windows Settings > Time & language > Typing.
2. Make sure Highlight misspelled words is turned on.
3. Optionally, enable Autocorrect misspelled words if you want common typos to be corrected automatically.

Enable connected experiences for Outlook

In Outlook versions that use Microsoft Editor for spellchecking, Connected experiences settings can affect the availability of spelling, grammar, and styling suggestions. If this feature is disabled, some Editor capabilities may be limited or unavailable.

Here's how to check and enable the setting in classic Outlook for Microsoft 365 and new Outlook for Windows.

Turn on connected experiences in classic Outlook 365

To check whether Connected Experiences are enabled in Outlook for Microsoft 365:

1. Go to File > Options > General > Privacy Settings.
2. In the Privacy Settings window, find the Optional connected experiences section.
3. Make sure Turn on optional connected experiences box is selected.
4. Click OK and restart Outlook.

Update Outlook

An outdated Outlook version can sometimes cause spell checking to malfunction. Installing the latest updates may resolve known issues and improve compatibility with Microsoft Editor and other proofing tools.

The update process differs depending on which Outlook version you're using:

• How to update classic Outlook
• How to update new Outlook for Windows

Repair Outlook

If spellcheck still doesn't work, some application files or components may be damaged. Repairing Outlook can help restore its normal functionality without requiring a complete reinstallation.

The repair options depend on your Outlook version:

• How to repair classic Outlook
• How to repair new Outlook for Windows

What to do if Outlook still doesn't check spelling

If you've tried the solutions above but Outlook continues to miss spelling mistakes, test the issue with a brand-new email containing several obvious errors. This can help you determine whether the problem affects all messages or just a particular draft.

If spelling works in a new message but not in an existing one, check the proofing language applied to that draft.

If the problem affects every message, your next step depends on the Outlook version:

• Classic Outlook: Check whether spelling works in another Office application, such as Word. If it doesn't, the issue may involve shared Office proofing settings or language tools. If spellcheck problems began after installing a specific add-in, try starting classic Outlook in Safe mode. If spelling checking returns to normal, a conflicting add-in may be responsible.
• New Outlook: Try Outlook on the web with the same account. If spellcheck functions there, the issue may be specific to the Windows application.
• Outlook on the web: Try another browser or Private browser mode to rule out browser-related problems.
• Microsoft 365 business accounts: If you use a work or school Microsoft 365 account and the problem persists, your IT administrator may also be able to check whether organizational settings or service issues are involved.