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An error occurred while sending mail. The mail server responded: Syntax error, command unrecognized.

  • 10 replies
  • 1 has this problem
  • 2 views
  • Paskiausią atsakymą parašė Matt

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I am unable to send emails all of a sudden. I keep getting this message.

"An error occurred while sending mail. The mail server responded: Syntax error, command unrecognized. Please check the message recipient ___________ @gmail.com and try again."

I am unable to send emails all of a sudden. I keep getting this message. "An error occurred while sending mail. The mail server responded: Syntax error, command unrecognized. Please check the message recipient ___________ @gmail.com and try again."

All Replies (10)

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please copy to clipboard and paste into a message the troubleshooting information from the help menu of Thunderbird.

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Hi Matt, I have tried putting what is written below into the help menu and this did not help at all. I spent an hour with customer service with my email provider. They could not figure out the issue.

An error occurred while sending mail. The mail server responded: Syntax error, command unrecognized. Please check the message recipient michael@_------_.com and try again.

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I will try again.

Go to the help menu. Click on troubleshooting information Press the copy to clipboard button Come to this forum. Paste into a reply on this thread Click the Post reply button.

Modified by Matt

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Here you go. Thanks

 Application Basics
   Name: Thunderbird
   Version: 31.7.0
   User Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0
   Profile Folder: Show Folder
             (Local drive)
   Application Build ID: 20150507114201
   Enabled Plugins: about:plugins
   Build Configuration: about:buildconfig
   Memory Use: about:memory
 Mail and News Accounts
   account2:
     INCOMING: account2, , (none) Local Folders, plain, passwordCleartext
   account3:
     INCOMING: account3, , (imap) imap.secureserver.net:993, SSL, passwordCleartext
     OUTGOING: smtpout.secureserver.net:465, SSL, passwordCleartext, true
   account6:
     INCOMING: account6, , (imap) mail.hover.com:143, plain, passwordCleartext
     OUTGOING: mail.hover.com:587, plain, passwordCleartext, true
 Crash Reports
 Extensions
 Important Modified Preferences
   Name: Value
     browser.cache.disk.capacity: 358400
     browser.cache.disk.smart_size_cached_value: 358400
     browser.cache.disk.smart_size.first_run: false
     browser.cache.disk.smart_size.use_old_max: false
     extensions.lastAppVersion: 31.7.0
     font.name.monospace.el: Consolas
     font.name.monospace.tr: Consolas
     font.name.monospace.x-baltic: Consolas
     font.name.monospace.x-central-euro: Consolas
     font.name.monospace.x-cyrillic: Consolas
     font.name.monospace.x-unicode: Consolas
     font.name.monospace.x-western: Consolas
     font.name.sans-serif.el: Calibri
     font.name.sans-serif.tr: Calibri
     font.name.sans-serif.x-baltic: Calibri
     font.name.sans-serif.x-central-euro: Calibri
     font.name.sans-serif.x-cyrillic: Calibri
     font.name.sans-serif.x-unicode: Calibri
     font.name.sans-serif.x-western: Calibri
     font.name.serif.el: Cambria
     font.name.serif.tr: Cambria
     font.name.serif.x-baltic: Cambria
     font.name.serif.x-central-euro: Cambria
     font.name.serif.x-cyrillic: Cambria
     font.name.serif.x-unicode: Cambria
     font.name.serif.x-western: Cambria
     font.size.fixed.el: 14
     font.size.fixed.tr: 14
     font.size.fixed.x-baltic: 14
     font.size.fixed.x-central-euro: 14
     font.size.fixed.x-cyrillic: 14
     font.size.fixed.x-unicode: 14
     font.size.fixed.x-western: 14
     font.size.variable.el: 17
     font.size.variable.tr: 17
     font.size.variable.x-baltic: 17
     font.size.variable.x-central-euro: 17
     font.size.variable.x-cyrillic: 17
     font.size.variable.x-unicode: 17
     font.size.variable.x-western: 17
     gfx.direct3d.last_used_feature_level_idx: 1
     mail.openMessageBehavior.version: 1
     mail.winsearch.firstRunDone: true
     mailnews.database.global.datastore.id: eac2cdea-5c53-4e92-b586-073246cf2f6
     mailnews.database.global.views.conversation.columns: {"threadCol":{"visible":true,"ordinal":"1"},"flaggedCol":{"visible":true,"ordinal":"3"},"attachmentCol":{"visible":false…
     network.cookie.prefsMigrated: true
     places.database.lastMaintenance: 1431961214
     places.history.expiration.transient_current_max_pages: 104858
     plugin.disable_full_page_plugin_for_types: application/pdf
     plugin.importedState: true
 Graphics
     Adapter Description: NVIDIA Quadro NVS 290
     Vendor ID: 0x10de
     Device ID: 0x042f
     Adapter RAM: 256
     Adapter Drivers: nvd3dumx,nvwgf2umx,nvwgf2umx nvd3dum,nvwgf2um,nvwgf2um
     Driver Version: 9.18.13.1115
     Driver Date: 1-31-2013
     Direct2D Enabled: true
     DirectWrite Enabled: true (6.2.9200.16492)
     ClearType Parameters: ClearType parameters not found
     WebGL Renderer: false
     GPU Accelerated Windows: 2/2 Direct3D 10
     AzureCanvasBackend: direct2d
     AzureSkiaAccelerated: 0
     AzureFallbackCanvasBackend: cairo
     AzureContentBackend: direct2d
 JavaScript
 Incremental GC: 1
 Accessibility
   Activated: 0
   Prevent Accessibility: 0
 Library Versions
     Expected minimum version
     Version in use
     NSPR
     4.10.6
     4.10.6
     NSS
     3.16.2.3 Basic ECC
     3.16.2.3 Basic ECC
     NSS Util
     3.16.2.3
     3.16.2.3
     NSS SSL
     3.16.2.3 Basic ECC
     3.16.2.3 Basic ECC
     NSS S/MIME
     3.16.2.3 Basic ECC
     3.16.2.3 Basic ECC
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what you pasted shows the outgoing server name rather strangely.

Go to Tools menu (alt+T) > account settings > outgoing server (SMTP) and check the server name. What is posted here looks like about half of the secure word is missing.

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The outgoing server is mail.hover.com whats strange out that? Please tell me how that should be different?

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Is there a IT phone number I can call? I really need to get this fixed. As I am only able to use the email on my cell phone

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No there is no phone number you can ring. There is this forum. Instead of ringing, how about actually defining the issue. Finally yuou let slip that it is your hover account that has a problem.

The error message would indicate that the email address is either incorrectly formatted or invalid. But try sending an email to devilsgatedrive@gmail.com and see if that gives the same error.

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Hi Matt,

It does not matter who or what email I try to send to. The same message comes up. I have a laptop I use a t home and all the server and outgoing server info is exactly the same as the account on my work computer. Yet it still does not work. Every time this message comes up

"An error occurred while sending mail. The mail server responded: Syntax error, command unrecognized. Please check the message recipient devilsgatedrive@gmail.com and try again."

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Looking over those settings again. Hover says use SSL on Port 465. You have the setting as none and Port 587.

Note here. Due to language semantics. If SSL/TLS does not work try START/TLS. Although it should be SSL/TLS some people incorrectly use the terms interchangeably.