Title: Configuration Error/Invalid mailbox syntax
Last modified: May 29, 2018

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# Configuration Error/Invalid mailbox syntax

 *  [merderein](https://wordpress.org/support/users/merderein/)
 * (@merderein)
 * [7 years, 10 months ago](https://wordpress.org/support/topic/configuration-error-invalid-mailbox-syntax/)
 * Hi there,
 * on the settings page, I get the “Configuration Error”: “Invalid mailbox syntax
   is used.”
    I’m totally sure it’s a false positive, because the email-adress provided
   is correct and working. But: There’s an umlaut in the domain of the email adress.
   May that be the cause of the wrong error message?

Viewing 4 replies - 1 through 4 (of 4 total)

 *  Plugin Author [Takayuki Miyoshi](https://wordpress.org/support/users/takayukister/)
 * (@takayukister)
 * [7 years, 10 months ago](https://wordpress.org/support/topic/configuration-error-invalid-mailbox-syntax/#post-10336276)
 * See [How to Resolve Configuration Errors](https://contactform7.com/configuration-errors/)
 *  Thread Starter [merderein](https://wordpress.org/support/users/merderein/)
 * (@merderein)
 * [7 years, 10 months ago](https://wordpress.org/support/topic/configuration-error-invalid-mailbox-syntax/#post-10339398)
 * unfortunately, this doesn’t help me at all. To be clear: For me everything is
   working fine, but the plugin is reporting an error. My assumption is, the check
   for the email-adress fails because of the umlaut in the domain.
    -  This reply was modified 7 years, 10 months ago by [merderein](https://wordpress.org/support/users/merderein/).
 *  [barnez](https://wordpress.org/support/users/pidengmor/)
 * (@pidengmor)
 * [7 years, 10 months ago](https://wordpress.org/support/topic/configuration-error-invalid-mailbox-syntax/#post-10340858)
 * Are you sure that the email field is required(*) in the form? e.g. `[email* your-
   email]`
    If the asterisk is missing then this can throw an error.
 *  Thread Starter [merderein](https://wordpress.org/support/users/merderein/)
 * (@merderein)
 * [7 years, 10 months ago](https://wordpress.org/support/topic/configuration-error-invalid-mailbox-syntax/#post-10341153)
 * yep, that is correct.

Viewing 4 replies - 1 through 4 (of 4 total)

The topic ‘Configuration Error/Invalid mailbox syntax’ is closed to new replies.

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 * 4 replies
 * 3 participants
 * Last reply from: [merderein](https://wordpress.org/support/users/merderein/)
 * Last activity: [7 years, 10 months ago](https://wordpress.org/support/topic/configuration-error-invalid-mailbox-syntax/#post-10341153)
 * Status: not resolved