As we know, there are many situations that lead to Outlook system errors or even fail to open. Errors are also different.

There is a human-induced error situation for Outlook. It's because we fail to transfer Outlook related files in the system disk, especially when there are other mailboxes, such as Hotmail, under the same login account. For example, we fail to cut the Outlook folder under C:\user\{username}\AppData\Local\Microsoft\Outlook into F driver. When we log into Outlook, system will prompt "Cannot start Microsoft Outlook. Cannot not open the Outlook window. Cannot open this folder collection. File access denied. You don't have access to C:\user\{username}\AppData\Local\Microsoft\Outlook\locou7_hotmail0.ost." What should we do in this situation?

At this time, we just need to cut and paste the C:\user\{username}\AppData\Local\Microsoft\Outlook\locou7_hotmail0.ost file and other .OST files in the directory to the desktop.

First, locate the corresponding files according to the above path:


Then, cut the corresponding .OST file:

And paste it to the desktop:


Try to start the Outlook again to see if it can be opened as expected.

If the issue persists, go to the Forums for better solutions.

Looking forward to your comments and suggestions!

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