Title: SMPT authentication error
Last modified: May 15, 2021

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# SMPT authentication error

 *  Resolved [greekinternet](https://wordpress.org/support/users/greekinternet/)
 * (@greekinternet)
 * [5 years ago](https://wordpress.org/support/topic/smpt-authentication-error/)
 * Hi all,
 * i have a vps with whm cpanel and litespeed web server. I host wordpress websites.
   I use wp smtp email plugin so i can avoid sending php emails. And every now and
   then i get an authentication arror and i have to manually reset the connection
   so many emails get lost.
 * The error i get in the plugin is
    2021-05-15 20:26:24 CLIENT -> SERVER: [credentials
   hidden] 2021-05-15 20:26:26 SERVER -> CLIENT: 535 Incorrect authentication data
   2021-05-15 20:26:26 SMTP ERROR: Password command failed: 535 Incorrect authentication
   data
 * But i am pretty sure that the password and username is corrent since when i reset
   the connection it successfully.
    Does anyone knows what is going on?

Viewing 2 replies - 1 through 2 (of 2 total)

 *  Plugin Support [Darshana](https://wordpress.org/support/users/darshanaw/)
 * (@darshanaw)
 * [5 years ago](https://wordpress.org/support/topic/smpt-authentication-error/#post-14445647)
 * Hi [@greekinternet](https://wordpress.org/support/users/greekinternet/),
 * Thanks for reaching out. Could you please try to authenticate your SMTP connection
   by using a 3rd party email client like [Mozilla Thunderbird](https://www.thunderbird.net/en-US/),
   and see whether your SMTP configurations are correct.
 * If you see the same error, you know that your SMTP configurations are incorrect
   and you need to locate the correct configurations.
 * If you’re able to connect to your SMTP email account using a 3rd party email 
   client (Mozilla Thunderbird), then you need to contact your hosting support with
   the WP Mail SMTP error log to identify this issue.
 * I hope this helps.
 *  Plugin Support [Darshana](https://wordpress.org/support/users/darshanaw/)
 * (@darshanaw)
 * [5 years ago](https://wordpress.org/support/topic/smpt-authentication-error/#post-14493565)
 * Hi [@greekinternet](https://wordpress.org/support/users/greekinternet/) – We 
   haven’t heard from you in about a week, so I’m going to go ahead and mark this
   ticket resolved. If you still have questions, though, please feel welcome to 
   continue the conversation.

Viewing 2 replies - 1 through 2 (of 2 total)

The topic ‘SMPT authentication error’ is closed to new replies.

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## Tags

 * [authentication](https://wordpress.org/support/topic-tag/authentication/)
 * [email](https://wordpress.org/support/topic-tag/email/)
 * [smpt](https://wordpress.org/support/topic-tag/smpt/)

 * 2 replies
 * 2 participants
 * Last reply from: [Darshana](https://wordpress.org/support/users/darshanaw/)
 * Last activity: [5 years ago](https://wordpress.org/support/topic/smpt-authentication-error/#post-14493565)
 * Status: resolved