Share this article

Improve this guide

How to fix error code 20 on Outlook

4 min. read

Updated onApril 11, 2024

updated onApril 11, 2024

Share this article

Improve this guide

Read our disclosure page to find out how can you help Windows Report sustain the editorial teamRead more

Key notes

Error code 20 is an error message that occurs for someOutlookusers when sending emails.

When they try to send an email, the application returns this error message,Outlookis unable to connect to the proxy server (errorcode 20).

This issue occurs when the software can’t connect with the proxy server. So does that error message sound familiar? If so, here are a few potential resolutions for error code 20.

How can I fix error code 20 on Outlook?

1. Check Windows’ Date and Time Settings

Error code 20 can often be due to a laptop’s or desktop’s date and time settings.

Check that Windows is displaying the correct time and date. If not, this is how you can configure the date and time settings inWindows 10.

2. Run a System File Checker Scan

The System File Checker tool in Windows fixes corrupt system files. Error code 20, like many other software issues, can be due to corrupted system files. This is how you can scan system files with the SFC tool in Windows.

3. Run an Anti-Virus Scan

It might also be the case that a virus or malware is responsible for error code 20. There are myriad third-partyanti-virus utilitiesyou can utilize to scan for viruses.

If you don’t have any anti-virus software currently installed, run an anti-virus scan with Windows Defender as follows.

In case you want a powerful antivirus solution with lots of protection features, you should use the comprehensive scans provided byESET HOME Security Essential.

4. Turn off Firewalls

Windows andthird-party software firewallsblock software from making connections.

Thus, a firewall blockingOutlookcould be responsible for the code 20 error, which is a proxy server connection issue. This is how you can switch Windows Firewall off.

Your third-party anti-virus utility might also have a firewall that’s blockingOutlook.

To switch its firewall off, right-click the anti-virus utility’s notification area icon on the right side of the taskbar.

You can usually select a disable or stop option to temporarily switch the software off from the context menu.

5. Reinstall Outlook

Uninstalling and installingOutlookagain is another potential fix for error code 20. ReinstallingOutlookwill give the application a fresh configuration and replace its program files.

You can uninstall the software by pressing the Win key + R hotkey and entering appwiz.cpl in Run.

Then clickOK, selectOutlookon the Programs and Features tab, and press theUninstallbutton. Thereafter, restart Windows before reinstalling the email application.

Those are a few fixes that might resolve error code 20 so thatOutlooksends emails again.

You can also try fixing the issue with theMicrosoft Support and Recovery AssistantorStellar Phoenixsoftware.

How to fix error code 20 on Outlook#

How can I fix error code 20 on Outlook?#

1. Check Windows’ Date and Time Settings#

2. Run a System File Checker Scan#

3. Run an Anti-Virus Scan#

4. Turn off Firewalls#

5. Reinstall Outlook#