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E-mail error: 421 Unexpected failure, please try later

Just accepted prompt to upgrade to NIS 2011 and now I am getting e-mail errors when sending e-mail from Outlook 2007.  The message: "421 Unexpected failure, please try later" appears in a Norton dialogue box, but the message still moves to Sent Items in Outlook.  Now I am left wondering whether the e-mail has actually been sent.  No message from Oultook to say anything is wrong.  Doesn't happen every time.

Any idea what might be causing this?

If I can't fix the problem is there an easy way to roll back to 2010? 



Re: E-mail error: 421 Unexpected failure, please try later

Hello Greg,

I have been experiencing the same thing today, postings elsewhere say the message usually comes from the Email server so the fault could lie with your provider, also it sometimes helps to disable outgoing Email virus scanning if the fault is within your own system.

A few experiments tell me that when this code is displayed the Email is lost, it shows in the Sent box, not in the Outbox, yet never reaches its intended destination.

At one point today around two thirds were getting lost, now I find the last  consecutive test 20 emails are getting through with no error messages suggesting the problem has been resolved (hopefully). My provider is Demon, a UK company, and their status line refers to recent resolved POP3 problems regarding Emails, but they can be over-optimistic in their pronouncements. Good luck.



Re: E-mail error: 421 Unexpected failure, please try later

Hello Greg

Welcome to the Norton Community Forum

As the above poster has mentioned, NIS serves as the messenger usually for email problems.  The problem usually exists with your ISP or the server that sends out the emails. Norton is just relaying that message to you. Since it doesn't happen all the time, I would tend to believe that it is a problem with what ever server sends out the emails. If you have to use ports other than 25 and 110, then you can disable to scanning of the emails since it will only be scanned if your ISP uses those ports. Thanks.

Success always occurs in private and failure in full view. Windows 7 Pro 64 bit NSBU Core Firmware 270 I E 11 Chrome latest one

Re: E-mail error: 421 Unexpected failure, please try later

I am getting the same 421 error message from NAV 2011 when I send e-mails from my newly installed Outlook 2010 on a Dell Studio laptop running Windows 7.   Everything I send does appear in my Sent  folder, and I have reason to think that at least some have actually gone out.  Still, I am unsure.  I have enabled delivery receipt in the Tracking option in Outlook to see if my e-mails are actually going out.  Is there anything else I can do to stop these 421 error messages from popping up by tweaking either Outlook or NAV?  Should either Symantec or Microsoft be fixing their software and sending us all a fix? 

Kudos2 Stats

Re: E-mail error: 421 Unexpected failure, please try later

A quick internet search for the 421 error seems to point to the email server.

However, since a few have noticed this after installing NIS / NAV 2011, perhaps this KB article will help.

This may prove to be a good temporary fix until the root cause can be isolated.

"Anyone who isn't confused really doesn't understand the situation."   Edward R. Murrow

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