How to resolve Yahoo Mail Error 999?

Yahoo is one of the most famous email communication services. Most of the people prefer Yahoo as it provides various additional features other than emails such as personal schedule organizer, chat messenger, and search engine. Creating and using Yahoo mail is also very simple. But still many face few errors while using Yahoo. A common Yahoo error reported by lots of users is Yahoo Mail Error 999. This error mostly appears when the user is using a shared internet connection. But you can get into this error due to various other reasons also.

Common reasons for Yahoo Error Code 999

1. Your internet browser is unable to accept the cookies from Yahoo 
2. You are using a shared internet connection
3. Your device is dealing with a malware infection
4. Some third-party software or application is conflicting with Yahoo pages are dealing with heavy traffic
5. Weak internet connection
6. You are sending or receiving a huge number of spam emails

Techniques for resolving Yahoo 999 Error

Allow browser to accept Cookies

Cookies store information on your device which allows you to access the pages quickly. While signing in to Yahoo, if you are getting any kind of error then you should check your web browser and configure your setting to accept the cookies.

Enabling cookies in Chrome

1. Open Google Chrome web browser
2. Click on the three vertical dots on the right-side
3. Go to Settings
4. Navigate to Advanced
5. Click on Privacy and Security 
6. Choose Content Settings
7. Now click on Cookies and enable the cookies option. Now again try to sign in for Yahoo mail

Enabling cookies in Firefox

1. Open your Firefox web browser
2. Go to Menu
3. Click on Options
4. Select Privacy and Security option
5. Tap the History button
6. Now select Use Custom setting for history option from the drop-down menu

Click on Accept cookies from the website button and then save the changes. Open a new tab and try signing in to Yahoo Mail. If you are still facing the same error then seek other solutions. 

Scan your PC

Yahoo error can also appear when your device has a malware infection. Sometimes malware blocks the network which can get you into this kind of issue. Use a reliable security software for scanning your PC. Make sure your antivirus can detect all types of malware like viruses, rootkits, worms, keyloggers, spyware, etc. Go to the dashboard of your antivirus and click on system scan. System scanning will take some time. Wait until the scanning process completes. Now restart your computer and try to sign in Yahoo email. 

Connect your device with another connection

You can also get this Yahoo error when you are using a shared connection. Weak internet connection is also a reason for Yahoo error. Try to connect your device to another internet connection. You should also try signing in Yahoo on another device. If you are unable to troubleshoot the error by using this technique then seek other solutions.

Try opening Yahoo on Supported Browser and OS

Yahoo is available for almost every browser and OS. But there are some features of Yahoo which you may not be able to access in every browser or OS. This error mostly appears when your browser is running out of date. Updating the browser may help to resolve your error.

Updating Chrome to Latest version

1. Open your Google Chrome browser and click on More (three vertical dots)
2. Go to Help button
3. Click on About Google Chrome
4. You will see Google Chrome Updates option

If you see a new update on Chrome then install it immediately

Once complete, relaunch your Chrome and then sign in to Yahoo

Updating Firefox to Latest Version

1. Open Mozilla Firefox browser
2. Go to Menu icon
3. Click on About Firefox

When the About window will open, Firewall will automatically start checking for the new update. Wait for completing the process and then click on the Restart button. Open a new tab and try signing in to Yahoo email. 

If your internet connection is weak then wait until the connection gets smooth. Otherwise, try connecting to your device with a smooth and reliable internet connection. Try logging in to Yahoo email; if you are still facing the same error then you should ask Yahoo technical team for troubleshooting your glitches. 

About This Author

Jean Hartman Joined: May 4th, 2020