When you are using the 64-bit version of Outlook, make sure you download the “MFCMAPI.exe.圆4” version instead. You can download MFCMAPI from its official development website on GitHub.

You can do some really great things with it, but you can also easily do large irreversible damage to your mailbox so it is important that you make a backup first and follow the below instructions carefully. MFCMAPI is a low-level editing tool to access your mailbox data. This is because the AutoComplete information is stored as a “hidden message” within your mailbox or pst-file. In order to backup and restore the AutoComplete cache you’ll need to make use of MFCMAPI. This means that when you are using an Exchange or account, you’ll have the same AutoComplete cache on each computer where you are using Outlook or Outlook on the Web (OWA) to access your mailbox.įor POP3 and IMAP accounts, this is not the case as this information isn’t synchronized with the mail server. Since Outlook 2010, the AutoComplete cache is being stored within your mailbox itself and is no longer a separate file. Where is the AutoComplete being cached now and how can I back it up in a way that I can also restore it in the future when needed? Now that I’m on Office 365, I no longer have this file but the AutoComplete feature still works. When I was still using Outlook 2007, I could back up my AutoComplete cache by copying the nk2-file and then reuse it on another computer.

Clear outlook 2016 image cache