Vista Email Issue and Fix
Vista SMTP Connection Issue - Error 0×8004210b
Have you had problems connecting to an SMTP server ?
Recently we have had email issues with Vista and Outlook with sending emails. Although we could receive emails via Outlook, they wouldn’t send. Most commonly, but not always, with the error 0×8004210b.
If you search for this error, you cannot find the solution anywhere, hence the reason for this post. The most common suggestions that we found are to turn off McAfee or Norton antivirus, delete and re-add the email account, re-install outlook or the most drastic of them all, re-install Vista. We tried all except the re-installation of Vista, and nothing worked (although we didn’t let Norton anywhere near our machines in the first place!)
Error 0×8004210b Vista SMTP issue Fix
After about 6 hours of searching, we finally found something buried away on the Microsoft technet forums. After fine-tuning it we could eventually send emails and this has also solved the error on our clients PCs.
Below, we have listed the fix that we used to solve the Outlook 0×8004210b SMTP issue:
1. Click the start menu and in the search box at the bottom, type cmd. This should bring up a list above the search box, with cmd.exe at the top.
2. Right-click on cmd.exe and click run as administrator. Depending on how your windows was set up, you may get a question box asking if you wish to continue or not. Press continue and you will get window with a black background, some white text and a flashing cursor.
3. Copy the line below into this window and press enter. Please be sure to copy it exactly, or if you wish, highlight the sentence below, right click and hit copy, then next to the flashing cursor, right click and press paste, then enter. You should get a message simply say “OK”.
netsh interface tcp set global autotuninglevel=disabled
4. Do the same as number 3, only use this code below:
netsh interface tcp set global rss=disabled
5. That is it done. You can now close the window an send those emails stacked in your outbox.
Although we have tried this 0×8004210b fix on 12 machines and it worked on all of them, both in the office and on clients machines throughout the UK, we don’t claim that this is the be all and end all of fixes, as your machine may have other issues that is preventing you from sending emails, but this worked in our case. If it works for you, please drop us a quick email to let us know.