Yahoo is also there with Google when it comes to security. There is an added layer of security to your Yahoo account called “Less Secure Apps”. When a third-party server tries to read or enter into your Yahoo mail account, then it gets blocked by Yahoo servers if their security is not up to Yahoo’s standard. Generally, it is not recommended to enable the “Less Secure Apps” option as enabling it option can be a potential risk to your Yahoo mail account and can put your account’s information in danger. We would strongly advise against it. You need also to check theyahoo mail pop server settings.
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