8 修复 Wi-Fi 呼叫错误 ER01 证书无效
Wi-Fi is a new and amazing technology that helps users make and receive calls over a wireless internet connection. Wi-Fi calling excludes the need to use a cellular network. Especially for smartphone users, this technology is a boon. It helps users operate the basic calling and texting functions of their smartphones from locations where cellular networks are hard to receive. However, amid so many perks of Wi-Fi calling, smartphone users can sometimes receive Wi-Fi calling error ER01 invalid certificate due to a number of reasons. If you are someone dealing with the same issue on your phone, then we have bought a perfect guide for you in which we will explain the error in detail, its causes, and multiple methods to fix error 01 invalid certificate. So, let us begin with our guide right away and move forward with resolving error 01.
How to Fix Wi-Fi Calling Error ER01 Invalid Certificate
Error ER01 on a smartphone indicates issues with connectivity and functionality with Wi-Fi calling feature. The error is usually encountered by organization workers who try to connect to other people over the company’s Wi-Fi network. This can be due to the IT department blocking employee activity on their company’s network. For the home Wi-Fi network, other reasons that can trigger the error include:
- Improper installment of your home Wi-Fi network.
- Disabled Wi-Fi calling feature.
- Outdated device software.
- Problems related to the Wi-Fi router.
- Problem with network settings of the smartphone.
There are some quick ways that can help you in fixing connectivity issues with Wi-Fi calling. Let us look at some authentic and troubleshooting methods below that will help you fix this error ER01 easily:
Method 1: Restart Router and Phone
The first measure to resolve error ER01 involves restarting your router or phone. Usually, the issue lies with the device or router that you use due to minor issues. These glitches can be resolved by simply restarting these devices. To restart your home router, you can follow the steps mentioned below:
1.找到 电源按钮 at the back of your router and press it.
2.现在， 断开 此 电力电缆 of your router and wait till the power is off.
3. After some time 重新连接 此 电力电缆 和 打开 此 路由器.
4. Let the connection 重建 并尝试 登录中.
要重新启动您的 Android device, you can refer to our guide, How to Restart or Reboot Your Android Phone?
方法 2：切换飞行模式 开和关
Another easy method to resolve Wi-Fi calling error ER01 invalid certificate is by turning on and off airplane mode. In most cases, the issue arises from the mobile network itself. In such a scenario, you can try resetting the cellular network which might help fix the said error. You can try turning on airplane mode on your device which will block the cellular network and stop your SIM card from working. Check the steps below to follow this method on your phone:
请注意： Steps in the doc are performed on Vivo 1920 Android phone.
1. Open your Android 个人设置 应用程序。
2。 启动 其他网络和连接 里面的选项。
3.现在， 开启 的选项 飞行模式.
4.一段时间后， toggle off Airplane mode.
The above steps will reset your cellular network and fix the Wi-Fi calling error as well.
另请参阅： How to Stop WiFi Turn On Automatically on Android
Method 3: Use Working Wi-Fi Connection
If you still have not been able to fix Wi-Fi calling error invalid certificate then you must ensure that your Wi-Fi is enabled and working. On connecting to a good Wi-Fi network, you will be able to operate Wi-Fi calling with excellent cellular signals. To enable Wi-Fi on your device, follow the steps as instructed below:
1. On opening the 个人设置 app of your device, tap on Wi-Fi.
2.现在， 开启 无线网络 按钮。
3. Tap on your preferred network from the 可用网络 名单。
4. 现在，检查 信号强度 of your Wi-Fi network and browse the internet to ensure it is working fine.
Method 4: Enable Wi-Fi Calling
To ensure you can call and text over a Wi-Fi network on your device, you need to make sure Wi-Fi calling is enabled in settings. This will help you resolve error 01 invalid certificate that often comes up due to connectivity issues. To enable Wi-Fi calling, follow the steps mentioned below:
1。 发射 个人设置 of your Android phone and navigate to the 搜索栏 在它。
2。 类型 Wi-Fi通话 在搜索栏中并按 输入.
3. 现在，点击 Wi-Fi通话 选项。
4. Finally, slide the 切换 至 打开 the Wi-Fi calling.
方法 5：取出并重新插入 SIM 卡
If you are unable to fix Wi-Fi calling error ER01 invalid certificate with the help of the above-given methods, you can try this simple workaround that involves removing and then reinserting the SIM card in your Android phone. Follow the steps below to place the SIM properly in your phone slot after removing it:
- 导航到 SIM托盘 on your Android phone and insert a pin in the hole to open the tray.
- 现在， take the SIM card out 的托盘。
- 接下来， 放置 SIM卡 正确 in the tray and push it back into the phone.
- 最后， 打开您的设备 and check if error ER01 has been resolved now.
另请参阅： Fix WiFi Authentication Error on Android
方法6：更新Android
There can also be an issue with the software of your Android device due to which you are facing a Wi-Fi calling error invalid certificate. To rule out this possibility, you must update your Android device to the latest version. Refer to our guide on How to Manually Update Android To Latest Version to properly attempt this method.
方法7：重置网络设置
One of the last methods that you can opt for in order to resolve error ER01 is to reset network settings. This method will automatically reset network adapters on your device which turns out to be very beneficial in resolving errors related to connectivity. Now, refer to the steps below to reset network settings on Android device:
1。 打开 个人设置 app and launch 系统管理 在你的手机上
2.接下来，点击 备份和重置.
3.现在，点击 重置网络设置 in the next menu.
4。 轻按 重新设置 屏幕上。
5. 完成后， reconnect to your Wi-Fi network and check if the error has been resolved.
另请参阅： 如何在 Windows、macOS、iOS 和 Android 上查看保存的 WiFi 密码
Method 8: Try Different Wi-Fi Network
The last method that can help you fix error 01 invalid certificate is to try a different Wi-Fi network altogether. In case none of the methods mentioned above has helped you in fixing the error, there is a high chance the problem lies with your Wi-Fi network. Therefore, to resolve it try connecting to some other Wi-Fi network and check if the Wi-Fi calling works or not. You can also try getting a new router if changing the network does not work.
常见问题解答（FAQ）
Q1. How can I enable Wi-Fi calling?
答。 You can enable Wi-Fi calling from the 设置 of your device. You can also refer to 方法4 to enable the feature on your Android phone.
Q2. Why is Wi-Fi calling feature not working on my phone?
答。 If the Wi-Fi calling feature is not working on your phone, then it can be due to the setting being turned off. The error can also arise from an issue with your Wi-Fi网络.
Q3. Why is Wi-Fi calling used?
答。 Wi-Fi calling is used to make 电话 并且寄出 文本 from a smartphone over the 随. This feature is extremely useful during no cellular network.
Q4. Is there any disadvantage of Wi-Fi calling?
答。 There are some disadvantages of Wi-Fi calling like poor signal strength, poor voice call quality, 和 掉线.
Q5. Which devices support the Wi-Fi calling feature?
答。 Smartphones like 三星盖乐世 S10、三星盖乐世 S20、三星盖乐世 S21, and others support the Wi-Fi calling feature.
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我们希望我们的医生 Wi-Fi calling error ER01 invalid certificate was helpful and guided you well about the causes and different methods that can help you fix this issue. Do let us know about your thoughts, queries, or suggestions by leaving your valuable comments below.
