This document explains how to fix Microsoft Outlook error code 0X80070021 if it is not working properly or throwing an error while installing, updating,  launching/opening, performing action like sending or receiving emails, configuring emails etc.

The error message looks like:

  • Error 0x80070021: The process cannot access the file because another process has blocked a portion of the file.

This solutions applies for following version of Microsoft Outlook:

  • Outlook 2007
  • Outlook 2010
  • Outlook 2013
  • Outlook 365
  • Outlook 2016
  • Microsoft Office (2013/365/2016)
Error InformationError Descripton
Error 0X80070021 Outlook Overview
0X80070021 Error Code Log
Avg. Time to Resolve Issue   30 mins
Difficulty Very Hard
Log Name: Microsoft Outlook <version> 4.42
Source: SSL Conflict
Event ID: 5457
Operating System
  • Windows 7
  • Windows 8
  • Windows 10
Level: System Level
User: <Outlook username>
Description:
  • Faulting Application Name: Microsoft Outlook <Application name>, version: 9.7.8211.69974, time stamp: 0×95017152
  • Faulting module name: Outlook  event.dll, version: 6.7.9836.45303
  • Exception code: 0xb05c071c
  • Fault offset: 0xe03f596c
  • Faulting process ID: 0×512
  • Faulting application start time: 0x08bdde1c31726702
  • Faulting application path: ~<userpath>
  • Faulting module path: ~C:\Program Files (x86)\Microsoft Outlook\<appname>
  • Report ID: e4b58c62-4269-28a1-2494-5811ccb1f824

Cause of 0X80070021 Outlook Error Code

  • Internet connectivity issue
  • Microsoft Outlook internal Application Conflict

Steps to resolve Outlook Error 0X80070021

Step 1: Check Windows Firewall Settings

1. Hold Win Key + R. Run Dialogue Box will open up.
2. Enter Firewall.cpl and Press OK.

3. Click on “Turn Windows Firewall On or Off
Turn Windows Firewall on or off4. In Private network Setting, select “Turn off Windows firewall (not recommended)
5. Do the same for Public Network Setting.
Disable Windows Firewall6. Press OK.
Note: After the issue is resolved you must turn the Windows Firewall on.

Step 2: Disable Proxy

1. In Start Searchbox type CMD
2. Click on CMD.
Office Resolve Error Proxy Check 3. In command Prompt Copy following commands (Simply select the command and hold ctrl+c and press ctrl+v in command prompt)

 netsh winhttp show proxy 

Check Proxy Setting

Note: You will need Administrator Access to Run the above command. Simply Right Click on CMD button and select “Run as Administrator

If you get the message “Direct Access (no proxy server)“, continue to the next step otherwise disable proxy from Network Settings.

 You can contact our 24×7 Live support for any help during the whole process. 

In most cases Outlook error code 0X80070021 should be resolved by following above steps. If however the issue still persists it means there is some critical issue with your system which needs to be fixed manually and is recommended to be done by an experienced Computer Technician.

You can chat one-on-one with one of our Outlook Support Representative 24/7 by clicking on the Chat button.

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Last Updated: 08/02/2016
Solution ID: 174062

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