How to Fix Yellow Triangle on Outlook New & Classic Client

Regular users of Microsoft’s email client may want to know how to fix yellow triangle on Outlook desktop app ASAP.

This error indicates that Outlook is facing trouble connecting to your email server. It can be the Exchange Online in the M365 cloud or an on-premise Exchange.

Don’t worry; this is a common issue in Outlook and can be solved with a few troubleshooting techniques.

Our guide contains well-tested strategies that will get rid of the annoying yellow triangle and get your Outlook back to its usable state.

Let us first figure out what this yellow triangle means.

Want to Fix Yellow Triangle on Outlook? Understand it First

It is a preliminary error indicator that tells if something went wrong with your email account. Which is most probably due to an account connection problem.

If for any reason Outlook fails to properly communicate with the server that stores the mail users start to see a yellow triangle-shaped caution symbol with a black exclamation mark at the center over the default Outlook icon.

However, an important difference to note is that in the new Outlook client, this indicator does not appear over the app icon. It shifts to appear next to the specific email account that is having the issue.

Moreover, it also changes its color to a hollow red triangle with a red exclamation in the center.

Mobile Outlook app users on both Android and iOS platforms may also see this issue in the form of a red triangle (often hollow) with an exclamation mark next to the account name in the account list.

You can find the exact error message by tapping on the affected account.

Now that the visual description of the error icon is understood let us list out all the possible reasons for its occurrence.

Why Do Users See Yellow Triangle on Outlook Clients?

Here is a non-exhaustive list of the usual suspects behind this problem. Knowing what causes the problem can help you isolate the issue and treat it more effectively.

Entered Incorrect Password: It might be that while the account set up you mistyped the account credentials. This is the number one reason to see a caution sign on the Outlook app.

Wrong Server Settings: Although Outlook auto-fetches the server details when you enter the account

Steps to Fix the Yellow Triangle Error on Outlook Client

Before you make any changes in Outlook double check your internet connection. Sometimes poor network speed may delay Outlook’s ability to fetch data and also affect our fixing process. So once the network is no longer an issue perform these steps.

Access Settings

• For Outlook Classic > File > Account Settings > Account Settings…
• If using Outlook New > Cog Icon > Mail > Accounts.
• On Outlook Mobile App > Tap your profile icon > Settings (Gear Icon) > Tap the affected account.

Tap on Change or Manage then Re-enter your password. Allow Outlook to verify the credentials

Ensure that this account does not have 2FA otherwise, your normal password won’t work. More on that is explained later in the blog.

You can also try to restart your device. Sometimes cache or memory refresh can solve this issue on its own, especially if the Outlook yellow icon is transient and not persistent.

Check the Microsoft outage chart to see if this is a widespread problem. In such cases, Microsoft releases special instructions so check out the techcommunity channel.

Disable Antivirus/Firewall Temporarily to See if It is the Reason

Outlook 2016’s yellow caution alert issue might not be due to any internal factor but an external program like your Antivirus/Firewall may be interfering with Outlook.

A temporary pause on the Firewall/Antivirus paired with an Outlook restart can easily tell if this is the actual issue.

You might have to re-configure your antivirus/firewall to allow Outlook’s connections.

Relation Between M365 Two Factor Authentication (2FA) and Yellow Triangle Icon on Outlook

For better account security Microsoft strongly recommends that you enable 2FA. This has a cascading effect that many users are unaware of. Accounts with 2FA may require app passwords to access apps like Outlook. This is a different one-time auto-generated view-only password.

So use Microsoft’s guide on how to make an app password and use it to set up your account in Outlook.

Advanced Troubleshooting on Outlook Profile

If by any chance none of the previous solutions work then your Outlook profile might be corrupt. For admins in an organization dealing with a huge influx of users with similar complaints, it’s recommended to get a copy of SysTools Microsoft 365 Backup Tool and safeguard user data before trying any advanced recovery methods.

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It may be that you encounter many Outlook ucrtbase.dll Crashes or Outlook.exe file re-installation throws in an entry point not found error. Do a careful evaluation of the error codes and see if they match the resolution steps given for the Outlook Error 0x80040600 guide.

Conclusion

Through this writeup, both admins and users saw how to fix the yellow triangle on Outlook 2016, 2019, Classic edition, New version, or mobile app. This is a small but frustrating problem that can reduce productivity. However, it can be resolved if proper steps are taken. So we recommend you start with the simple procedure like closing and opening Outlook again and move on to more complex ones from there only if your problem still persists.

Moreover, if you feel that this is a significant enough problem and may lead to data loss you can use the backup solution we gave earlier.

Frequently Asked Questions

Q. Does changing my password outside of the Outlook client cause this issue?

A. Yes this is a highly likely scenario that during web login or any other login attempt you may have used the forgot password mechanism and updated your current outlook password.  For security purposes Microsoft makes you re login in very client where your account was connected previously. If you fail to do that the account and Outlook itself may show the caution sign.

Q. When should I contact my email administrator or Microsoft support?

A. After trying all basic and intermediate troubleshooting steps.

• If you suspect a server-side issue (e.g., mailbox quota, account locked).
• If you’re in a corporate environment and your IT department manages your email.
• If the problem persists for an extended period (e.g., more than a day).
• If you see error messages that you don’t understand or that suggest a serious problem.
• If you are not comfortable making changes in the advanced settings.