Outlook - set of folders cannot be opened - unable to fix this error via any method

Anonymous
2021-11-14T11:31:50+00:00

Hello,

i have an issue i've been unable to resolve for a few weeks, maybe even months now.

I was setting up a new All-in-One PC for an employee at a company we do IT support for. The setup went without a problem, he has Windows 10 OS and a Microsoft 365 Business Standard license.
A week or two go by and he informs me hes getting the known error when opening Outlook - The set of folders cannot be opened. To simplify, I decided to create another mail profile. This seemingly resolved the issue but I get another call from him a few days later saying the same problem has occured. We repeat the process and create a 3rd email profile. The same error pops up again, even sooner (maybe a day or two). The most peculiar thing is (he has 3 or 4 profiles at this point) that if I keep swapping between the profiles randomly and trying to start Outlook, lets say 1 in 20 times it actually starts up.
So I start troubleshooting the issue with everything I could find on google.

A list of possible solutions I've tried to far:

  1. Starting outlook in safe mode - still does not start
  2. Disabling add-ins - did not help
  3. Reinstalling Office365 - did not help
  4. Repaired Office365 - did not help
  5. I believe i've tried some other repair/scan tools but nothing ammounted to anything

At this point I figured it might have to be something on his domain profile, so we delete the local profile and recreate it, the error still appears.

We replace his new PC with his older one on which everything works without any problems. We try creating a local account on his co-workers account, Outlook works fine there.

So a few days ago I decide to just reinstall the windows again hoping it would solve the issue (I did the reset with keeping the personal files). I install Outlook, it opens up. To test it out I close it down and try to re-open it - im hit with the error. I create a new profile again and manage to open Outlook exactly once, when i close it down and reopen the error hits me again. Just to make sure i repeat the process a 3rd time, same result - so in short whenever i create a new profile i manage to start up Outlook exactly once before the error appears.

At this point I'm out of ideas on what to try, I plan to bring another machine, domain join it and create his profile on it to see if the problem repeats - so far this only happens on 1 machine, on 2 others in the same domain it works fine.

Is there any reason this could be a hardware issue? Because thats the only thing that somewhat makes sense to me altho on the other hand I can't imagine it being hardware related. The OS and O365 are all updated.

Thanks for any advice or input in advance

Outlook | Windows | Classic Outlook for Windows | For home

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Anonymous
2022-02-21T18:49:57+00:00

Had the same problem

These steps fixed it.

If updating the Outlook application was not able to fix the error in Outlook “the set of folders cannot be opened” then you have to recreate the Outlook email profile. This method has helped many users to fix the error. 

  1. Go to the Windows search bar and type regedit. This will launch the Registry Editor.
  2. Then, navigate to Computer\HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Outlook\Profiles (Outlook 2019,2016)
  3. Now delete all the folders listed under Profiles.

Note: If you are using a different version of Outlook this will change as follows. Computer\HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\15.

  4. Restart the computer.

  5. Relaunch Outlook and recreate your email profile.

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  1. Anonymous
    2023-06-14T23:12:05+00:00

    No joy. Tried creating a new MS acct and got the same result. Thanks for trying.

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  2. Anonymous
    2023-06-14T14:46:50+00:00

    Hello Alberto,

    Thanks for the solution above. I have just been able to resolve the 'set folder cannot be open' problem with my Outlook even after re-installing Microsoft 365.

    I have set up a new profile and gotten into Outlook, but now I have another problem. When I hit the send and receive to download my email from our server it cannot pull down my emails. An error in the window came up and I still left with my profile, unable to pull down my emails.

    The error reads as follows:

    The operation failed. An object cannot be found.

    I have reassigned the new .pst/.ost data file to my backed-up Outlook data file but this operation is still not pulling down my email.

    A little history of how I got here. Two nights ago, I commenced a system back-up to OneDrive which resulted in the movement of all files on my Desktop and Document folder. Prior to the Set Folder issue my Outlook profiles were linked in C: drive but once the back-up and syncing with OneDrive begun it was not connected to the synced folder. It did so until I paused syncing and rebooted my PC. My goal with the back-up was to free up space on my C: Drive.

    Now with all files synched, OneDrive paused to save on data cost and Set Folders resolved, I still cannot get to use Outlook.

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  3. Anonymous
    2023-04-06T01:58:10+00:00

    I followed the path but there is no profiles folder in outlook?

    have i missed something here?

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  4. Anonymous
    2023-01-10T23:47:44+00:00

    OMG - this worked. THANK YOU!!! I have MS Office Prof'l 2021 - THIS WORKED!!!!!

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