Vista SMTP Connection Issue in Outlook – Error 0x8004210b!

Recently many Outlook users have encountered email issues with Vista while sending mails through it. Although people can easily receive mails via Outlook but sending is simply not possible with a common error 0x8004210b. Most common suggestion to resolve this issue is to turn off the antivirus, delete and then re-add the email account. Reinstall Outlook application in most drastic situation but in case nothing works then you can go with PST Repair Vista software to repair the corrupt PST and recover the data stored in it.

Fix 0x8004210b Error SMTP Vista Issue

The below listed steps will help you to fix the Outlook 0x8004210b SMTP issues –

• Click Start > Search and in the search box at the bottom type ‘cmd’.
• This will bring the list of search items with cmd.exe at the top.
• Now right click on the ‘cmd.exe’ and click ‘Run as administrator’.
• Now as per the Windows set up, you will get a question box asking, if you wish to continue or not.
• This will bring a window with a black background with a flashy white cursor.
• After that copy the line below at the command prompt and press ‘Enter’ –
  “netsh interface tcp set global autotuninglevel=disabled”
• Make sure that you copy the line exactly as it is. When you get a message related to it, then just say ‘OK’.
• Once it is done close the window and the send those email stacks to outbox.

This is the tried fix of 0x8004021b error that occurs in Outlook in Windows Vista. So, you can use these steps to resolve your Outlook issue as well.