The error blames olk.exe — the new Outlook — for not closing your data file. Classic Outlook and the new Outlook are fighting over the same PST. Remove the conflict in the right order and the folder opens again.
You clicked a mail folder and got a wall: Cannot display the folder, with a line saying olk.exe exited without properly closing your Outlook data file. It looks like a corrupt PST, and the internet will happily sell you repair tools for it. But watch the name inside the error — this is a conflict between the two Outlooks on your PC, and the fix is mostly about removing that conflict, not repairing the file. Follow the cards in order.
Cannot display the folder. Microsoft Outlook cannot access the specified folder location. olk.exe exited without properly closing your Outlook data file. The data file needs to be checked and repaired before it can be used again.
Most people read only the first three words — Cannot display the folder — and start searching for PST repair tools. Read the whole message instead. The program it blames is olk.exe, and olk.exe is the new Outlook app. In other words, this message is classic Outlook telling you: the new Outlook had this data file open and did not close it cleanly. The problem is not a dead PST. The problem is two Outlooks fighting over one data file — exactly the conflict shown in the video.
This happens on PCs where both apps are set up with the same mailbox and the same PST file is also added inside classic Outlook under File, then Account Settings, then the Data Files tab. Each app opens and locks the file in its own way, and sooner or later one of them exits without releasing it properly.
No repair works while one of the two apps still holds the file in the background. Closing the window is not always closing the app, so check properly:
olk.exe or OUTLOOK.EXE in the list, select it and click End task.Skipping this step is the most common reason the fix appears to fail. If a process is still running, every change you make next is tested against a file that is still locked.
This is the fix demonstrated in the video. The same PST should not sit inside classic Outlook's data file list while the new Outlook is also using that mailbox:
Important: Remove here only detaches the file from the profile. It does not delete the PST from your disk and it does not delete a single email. The file stays exactly where it was — Outlook simply stops fighting over it.
After removing the duplicate entry, use Start → Power → Restart. On Windows 10 and 11 a normal Shut Down is partly a hibernation trick (Fast Startup), so it can carry the same locked state into the next boot. Restart clears it fully. When the PC comes back, open only one Outlook and click the folder that showed the error. In most cases it now opens normally, because nothing else is holding the data file.
The error returns if both apps keep opening the same file, so decide once:
One data file, one app. That single habit prevents this whole error class.
If the error now appears inside the new Outlook itself even when classic Outlook is closed, repair the app the way Microsoft documents:
The video shows the conflict live — where the duplicate PST sits in Data Files, and removing it to clear the error.
▶️ Watch Full VideoNo. The error means Outlook could not open the folder because the data file was left in a not-closed state by the other app. Your mail is still in the file and on the server. Nothing in this guide deletes mail — the Remove button in Data Files only detaches the file from the profile.
Because olk.exe is the new Outlook, and it was the program that last had the data file open without closing it properly. Classic Outlook is simply the messenger — it found the file in that state when you clicked the folder.
Yes, both apps can live on one PC. What they cannot do safely is share the same PST data file day to day. Keep each data file attached in one app only, and this conflict does not come back.