Outlook Spell Check Not Working? Fix the Main Causes

If Outlook spell check is not working, first check whether you are using classic Outlook or the new Outlook, then confirm spelling is enabled and the message has the correct proofing language. In classic Outlook for Windows, use File > Options > Mail > Spelling and Autocorrect; in new Outlook, look for Microsoft Editor while composing a message.

First identify which Outlook you are using

Outlook has more than one Windows interface, and their writing tools are not controlled in exactly the same place. Classic Outlook is the desktop application with a File tab and a full set of Outlook Options. New Outlook has a more web-like interface, usually with a Settings gear, and shares much of its behavior with Outlook on the web. A fix for one version may not apply to the other.

If you are unsure, look at the top-left area of the app. A File tab that opens a backstage screen with an Options button usually means classic Outlook. A Settings gear and a simplified layout generally indicate new Outlook. Outlook in a browser is Outlook on the web; its editor is also different from the classic desktop proofing controls.

This distinction matters because a missing red underline does not always mean spell checking is broken. Classic Outlook can check spelling as you type and before sending, while the newer interface uses Microsoft Editor features that can depend on the current compose view, language, and account setup. Test spelling inside a new message rather than judging by the contents of your Inbox: Outlook does not normally proofread every message you receive.

Turn on spell check in classic Outlook for Windows

In classic Outlook, check both the automatic proofing option and the pre-send option. Open File > Options > Mail, then select Spelling and Autocorrect. In the Editor Options window, choose Proofing and confirm that Check spelling as you type is selected. Back in the Mail options, confirm that Always check spelling before sending is selected if you want Outlook to run a check when you send a message.

The two settings do different jobs. The first controls the red spelling indicators while you write. The second asks Outlook to check the message during sending, even if you did not notice or use the underlines. If you only want a one-time check, open a message and press F7. You can also use the spelling command on the Review tab when it is available in the message window.

For a quick test, compose a new email and type a deliberately misspelled word such as “recieve” in the message body. If it is not underlined, click in the body and confirm the proofing language and options described below. If the word is underlined but no check appears when sending, the pre-send setting may be off, or the message may be in a format or editing state that behaves differently.

Use Microsoft Editor in new Outlook and Outlook on the web

New Outlook and Outlook on the web use Microsoft Editor for writing suggestions rather than exposing the classic Outlook proofing dialog. Open a new message and look for Editor or its writing-suggestions controls in the compose toolbar or ribbon. If the control is present, open it to review spelling suggestions and available settings. The exact layout can change as Microsoft updates the interface, so a control may be in a different place or not shown in every account.

If Editor does not flag an obvious typo, first make sure you are typing in the message body and not a field that is not being checked. Then verify the language assigned to the text, close and reopen the compose window, and try a fresh message. In Outlook on the web, also consider whether a browser extension is changing the editor or interfering with page scripts: test in a private window with extensions disabled, if your organization allows it.

Do not assume that enabling automatic spelling in Windows will switch on every Editor feature in new Outlook. Windows language settings can affect available proofing languages, but the newer Outlook editor has its own controls and may offer different suggestions from classic Outlook. If Editor is missing entirely, install available Office updates and check whether your organization manages the app or disables connected writing features.

Set the correct proofing language

A wrong language is one of the most common reasons spell check appears to do nothing or marks correct words as errors. For example, a message set to English (United States) may flag British spellings such as “organise,” while a message set to French will treat ordinary English words as misspellings. Outlook can also inherit a language setting from selected text, a template, or copied content.

In classic Outlook, click in the message body, select the text if needed, and open Review > Language > Set Proofing Language. Choose the language you are writing in. Check that Do not check spelling or grammar is not selected, then confirm the dialog. If you want the language for future messages, set it as the default where that option is available. For new Outlook or the web version, use the language or Editor controls shown in the compose experience.

Also check that proofing tools for the language are installed. In classic Outlook, File > Options > Language shows Office authoring languages and proofing availability. Windows language support can be reviewed under Settings > Time & language > Language & region. If the language is listed as needing proofing tools, follow the Office prompt to install them; simply selecting a language does not guarantee the corresponding dictionary is present.

Check text formatting and dictionary behavior

Sometimes only part of a message is not checked. That often points to formatting or language assigned to that text rather than a problem with Outlook as a whole. Text pasted from a website, an older email, or a document can carry its own proofing language and formatting. Select the affected passage and inspect its language setting. As a diagnostic, type a short test sentence directly into a blank message instead of pasting it.

Messages composed in plain text or HTML can have different editing features, but changing the format is not a universal spell-check repair. In classic Outlook, you can inspect a message’s format from the Format Text tab. If the problem happens only in a particular template or reply, test a new blank message before changing account-wide settings. This helps distinguish an inherited template setting from a disabled proofing option.

Custom dictionaries can create the opposite problem: a misspelled word may not be underlined because it was previously added as an accepted word. If Outlook marks a correct name or technical term, right-click the underlined word and choose Add to Dictionary when that option appears. Be cautious about adding whole phrases or uncertain spellings; a custom dictionary tells the proofreader to accept that entry, not that it is correct. If a bad entry was added, review the custom dictionary through the Proofing options in classic Outlook.

Troubleshoot when the usual settings are correct

Work through these checks in order so you can identify whether the fault is limited to one message, one Outlook version, or the Office installation:

Start a new blank message and type a known misspelling in the body. Avoid testing only in the subject line or a pasted paragraph.
Confirm the message language and check that “Do not check spelling or grammar” is not enabled for the affected text.
Close Outlook completely and reopen it. Then install available Microsoft 365 updates from File > Office Account > Update Options > Update Now in classic Outlook.
If classic Outlook still fails, open Windows Settings > Apps > Installed apps, select Microsoft 365, choose Modify, and try Quick Repair. If necessary, consider Online Repair, which takes longer and may require an internet connection.
For new Outlook or Outlook on the web, test another browser or a private window if permitted, and check whether Editor works in a fresh message. This can help identify an extension or browser-specific issue.
If the issue affects a work or school account, ask your Microsoft 365 administrator whether policy, add-ins, or a managed language configuration is involved.

Repairing Office is more disruptive than checking settings, so save open work first and try it only after the simpler tests. A repair is unlikely to help if the problem occurs only in one message with an incorrect proofing language. Likewise, reinstalling Outlook is rarely the best first step when a single checkbox or a missing language tool can explain the behavior.

What spell check can and cannot catch

Spell check compares words with language dictionaries and may use context to suggest corrections. It can catch a typo such as “teh,” but it cannot reliably determine whether a correctly spelled word is the one you intended. “Their” and “there” are both valid spellings, for example, and a sentence can pass a spelling check while still being confusing or factually wrong.

Microsoft Editor may also offer grammar, clarity, or writing suggestions, depending on the version, language, account, and available settings. Those suggestions are separate from basic spelling checks and should be reviewed rather than accepted automatically. For names, product terms, addresses, and technical language, a red underline may simply mean the dictionary does not recognize the entry.

For important messages, read the final text yourself, especially names, dates, numbers, recipients, and attachments. A successful spell check does not verify that an email is going to the right person or that its claims are accurate. If Outlook’s checker remains unavailable, you can draft or review text in Word or another editor with proofing enabled, then paste it into Outlook and check the final message again for formatting.

Frequently Asked Questions

Why does Outlook spell check work before sending but not show red underlines?
In classic Outlook, Always check spelling before sending and Check spelling as you type are separate settings. Confirm both under File > Options > Mail > Spelling and Autocorrect > Proofing. Also check that the text is not set to Do not check spelling or grammar.

How do I manually spell-check an Outlook email?
In classic Outlook, click in the message and press F7, or use the spelling command on the Review tab if it is shown. In new Outlook, use Editor in the compose toolbar or ribbon when available. Review suggested changes before sending.

Why is Outlook marking correct words as misspelled?
The message may be assigned the wrong language, the word may be a name or specialist term missing from the dictionary, or the chosen spelling variant may differ from your language setting. Check the proofing language before adding a word to a custom dictionary.

Does Outlook check spelling in incoming emails?
Normally, spell check is for text you compose, not a tool that automatically proofreads every message in your Inbox. To review received text, copy it into a document or another editor with proofing enabled, while respecting any privacy or workplace rules that apply.

Why does spell check work in Word but not Outlook?
Word and Outlook can use different app settings, compose experiences, or message language assignments. Check Outlook’s own proofing controls and test a new message. If only Outlook fails after settings and language tools are confirmed, update or repair Office, or ask your administrator about managed settings.

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