Error 452 4.1.0 TLS and Authentication required

Hello,

I receive the message: "Error 452 4.1.0 TLS and Authentication required"

Error 452 refers to exceeding limit of sent/recipient (not the issue in this case)

server=smtp.comcast.net

default smtp port=25

I'm wondering if using port 25 is the issue.

Any suggestions appreciated.

Responses

CC_Alisha

Contributor

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20 Messages

3 years ago

Hello, @user_85e6c4 Thank you for asking your question in our Comcast Business Support Forum. I am sorry for the troubles you are having with your email. In an effort to providing our customers with the greatest security when using email, Comcast recommends the use of industry-recommended port 587 with TLS/SSL enabled. Have you attempted to use port 587 instead?

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user_85e6c4

New Member

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3 Messages

@Comcast_Alisha

Thank you for the reply, Alisha. I changed port to 587 and now receive message: "Error 550 5.1.0 Authentication required"

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3 years ago

0

Comcast_Katie

Official Employee

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34 Messages

Thank you for providing us with that update and trying that out for us, we'll ensure you get the support you need on this! If we may ask, what are you doing when you get this error? Do you get it as soon as you log into your email, when trying to send an email, etc..?

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3 years ago

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user_85e6c4

New Member

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3 Messages

Katie,

I receive error when using third-party program to send an email, had no issue for years until two days ago.

Thanks

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3 years ago

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Comcast_Aldrik

Official Employee

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27 Messages

Thank you for clarifying that! We recently updated our email settings regarding third-party email clients. For troubleshooting purposes, are you able to log into Xfinity Connect https://comca.st/3CnWsik and verify that the box underneath "Third Party Access Security" is checked?

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3 years ago

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CC_Morgan

Gold Problem solver

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49 Messages

Hi! Thank you for posting. Please take a look at this link for me, and let me know if helps: https://www.xfinity.com/support/articles/third-party-email-access.

I no longer work for Comcast

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2 years ago

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