How to Fix: Reset Outlook, Start Over (New Install)

Infopackets Reader Mike J. writes:

" Dear Dennis,

Thanks for your article on 'cannot start outlook, cannot open window'. I have a similar problem. I recently had to format my machine and reinstall Windows 10, then reinstall Office 365. I'm now at the part where I want to set up my email account with Outlook, but I've made a huge mistake during the setup: I told Outlook that my email address is associated with a Microsoft Exchange server instead of IMAP. Now I can't undo the changes!

Here's what's happening: when I try to launch Outlook, it keeps asking for my login credentials repeatedly and I simply cannot get passed it. What's worse is that Outlook won't let me delete the Microsoft Exchange account because it says I need to have another account as the default account and I don't have any other email addresses to use! Furthermore, I can't specify IMAP on the existing account because there is no option to do so. I've also tried adding a new account using the same email address, but Outlook says that this is a duplicate account and I can't continue on. I've tried deleting the data file associated with my email address but it won't let me do that either!

Unbelievable! All I want to do is reset Outlook and start over from scratch and create a brand new user profile, but there is NO option to do that. I've read many guides online that say you can delete the existing account and add a new one, but - believe me - Outlook will not let me, no matter how hard I try. How in the world am I supposed reset Outlook and start over like a new installation? "

My response:

I asked Mike if he would like me to connect to his machine using my remote desktop support service in order to have a closer look at the problem.

Below I will discuss my findings.

How to Fix: Reset Outlook, Start Over (New Install)

After much research on the subject, the only way I could get this to work is through a registry edit. The great thing about this method is that it doesn't require an MS Office DVD or installation file in order to continue. Some posts I came across suggested uninstalling and reinstalling MS Office to fix the problem (which would require the DVD or install file), but chances are that a reinstall would not remove your old Outlook user profile because this information would most likely remain in the registry.

The script below will kill the Outlook task if it's running, make a backup of your Outlook settings (in case you need to get it back for some reason), then reset Outlook to factory settings allowing you to start over and create a new profile. Note that I tested this script with Office 365 but it should work with all other versions of Outlook.

To do so:

1. Click Start, then type in "cmd" (no quotes); wait for "CMD.EXE" or "Command Prompt" to appear in this list, then right click it and select "Run as Administrator".
    
2. Use the text below to highlight it with your mouse:
   
   taskkill /f /im outlook.exe
   ping -n 5 localhost >nul
   reg copy HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office.bak /s /f
   reg delete HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office /f
   echo this is a dummy line
    
3. Right click the above highlighted text and select "Copy" from the dialogue menu.
    
4. Go to the command prompt window you opened up in Step #1 above, and right click in the middle of the window and select "Paste". The text you copied in Step #2 above should now be output to the command line, and Outlook will be reset.
    
5. Launch Outlook from the Start menu and it should ask you to set up a new user profile.

That should fix it!

How to Undo the Outlook Reset

If you need to get your old user profile(s) back and you want to undo the reset, follow these instructions:

1. Click Start, then type in "cmd" (no quotes); wait for "CMD.EXE" or "Command Prompt" to appear in this list, then right click it and select "Run as Administrator".
    
2. Use the text below to highlight it with your mouse:
   
   taskkill /f /im outlook.exe
   ping -n 5 localhost >nul
   reg query HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office.bak >nul
   if %ERRORLEVEL% EQU 0 reg delete HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office /f
   reg copy HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office.bak HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office /s /f
   reg delete HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office.bak /f
   echo this is a dummy line
    
3. Right click the above highlighted text and select "Copy" from the dialogue menu.
    
4. Go to the command prompt window you opened up in Step #1 above, and right click in the middle of the window and select "Paste". The text you copied in Step #2 above should now be output to the command line, and Outlook will be reset.
    
5. Launch Outlook from the Start menu and it should ask you to set up a new user profile.

I hope that helps.

Additional 1-on-1 Support: From Dennis

If all of this is over your head, or if you need help getting Outlook to work, I can help using my remote desktop support service. Simply contact me, briefly describing the issue and I will get back to you as soon as possible.

About the author: Dennis Faas

Dennis Faas is the owner and operator of Infopackets.com. With over 30 years of computing experience, Dennis' areas of expertise are a broad range and include PC hardware, Microsoft Windows, Linux, network administration, and virtualization. Dennis holds a Bachelors degree in Computer Science (1999) and has authored 6 books on the topics of MS Windows and PC Security. If you like the advice you received on this page, please up-vote / Like this page and share it with friends. For technical support inquiries, Dennis can be reached via Live chat online this site using the Zopim Chat service (currently located at the bottom left of the screen); optionally, you can contact Dennis through the website contact form.