However, if the registry entry doesn’t exist, it creates, it then saves a copy of the attachment in the folder.įor example, let’s say your running Windows 10 and Outlook for Microsoft 365 like me. If Outlook finds a registry entry for the OLK folder, it saves the file and opens it for you. To do this, it checks the registry to see if Outlook has already created a temporary folder (aka – the outlook OLK folder) for this use. When you open file attachments from an email, Outlook needs to save the files somewhere on your hard drive before opening the file. Windows 10 running Outlook for Microsoft 365Īs you can see from the screenshot, the OLK temporary folder is located at: C:\Users\Steve\AppData\Local\Microsoft\Windows\INetCache\Content.Outlook\CM88YL7V\ Background – What is the OLK folder, and why is it so hard to find?
Outlook 2019 & O365: HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Security Outlook 2016: HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Security
Outlook 2013: HKEY_CURRENT_USER\Software\Microsoft\Office\15.0\Outlook\Security Outlook 2010: HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\Security Outlook 2007: HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\Security Outlook 2003: HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Outlook\Security Outlook 2002/XP: HKEY_CURRENT_USER\Software\Microsoft\Office\10.0\Outlook\Security Outlook 2000: HKEY_CURRENT_USER\Software\Microsoft\Office\9.0\Outlook\Security Outlook 98: HKEY_CURRENT_USER\Software\Microsoft\Office\8.5\Outlook\Security To determine the spots where folders got created, open the Windows registry using regedit.exe and look for the Registry key OutlookSecureTempFolder using the map below: Outlook 97: HKEY_CURRENT_USER\Software\Microsoft\Office\8.0\Outlook\Security The good news is, it’s simple to find no matter the version of Outlook, including Outlook 2010, Outlook 2013, Outlook 2016, Outlook 2019, and Outlook for Microsoft 365 (or O365). Depending on the operating system, version of Outlook, and the user currently logged in, the OLK temporary folder gets created in a different location.