The file outlook.ost could not be accessed.


The file C:\Documents and Settings\username\local settings\application data\Microsoft\outlook\outlook.ost could not be accessed.

Unable to display the folder,[path]Outlook.pst could not be accessed, access denied.


Errors such as these are most commonly caused by errors in the .OST local cache of an Outlook mailbox.  To resolve this, I’ve had quite a bit of luck with simply deleting or renaming the .OST file to .OLD.  You can find the file, by default, in the following locations:

Windows XP:

C:\Documents and Settings\Local Settings\Application Data\Microsoft\Outlook\Outlook.ost

Windows Vista:


Note:  If you don’t see some of the folders, they may be hidden.  To view hidden files, open Folder Options in Control Panel, click the View tab, and select “Show hidden files and folders”

Second note:  The file name for the .OST file corresponds to the name of the Outlook profile.  By default, this is Outlook.ost.  However, your mileage may vary depending on what the Mail Profile was named when initially created.  You can check the name of the Mail Profile by opening Control Panel and clicking the Mail icon.