One of the great things about online email services like Gmail is that you never have to worry about things like autocomplete, because all your contacts are stored in the cloud, and Gmail automatically creates a giant index of everyone who sent an email to you, or everyone you email. When you start typing a name or email address, it magically displays all matching contacts!
Not so with Outlook 2016 or any previous version of Outlook. Nothing is stored in the cloud, so everything is based on local files. The same is true for the autocomplete suggestion feature. Basically, every time you enter a name or email address in Outlook, it saves it to a file, and so the next time you enter that name or email address, it fills it in automatically.
Note. If you work in a corporate environment, then technically your contacts are stored in the cloud (Exchange server).
If you’ve been using Outlook for years, your autocomplete database can be huge, and if it suddenly stops working, emailing someone is a real problem! Sometimes AutoComplete stops working due to problems with the PST file, and sometimes due to updating to a newer version of Outlook from previous versions. I also ran into an issue where autocomplete would work for one Outlook session, but when you close it and reopen it all the entries are gone.
In this article, I will share several methods that I have learned over the years to fix the Autocomplete issue in Outlook and how to transfer AutoComplete suggestions from one Outlook to another.
Repair PST file
A common issue where autocomplete stops working has something to do with your PST file. The first thing to try is repair the PST file and see if the autocomplete entries come back or stop dumping. You can do this by navigating to the following folder on 64-bit Windows
– / C: Program Files (x86) Microsoft Office Office14
and run scanpst.exe. Please note that the path may differ depending on your version of Office. For example, if you are using a 64-bit version of Office and newer, then the path might be C: Program Files Microsoft Office Office15. Additionally, newer versions of Office may store the file in the following location:
C: Program Files Microsoft Office root Office16
Click Browse and navigate to your PST file. If it is in the default folder, go to C: Users Username AppData Local Microsoft Outlook. By default, it should be named Outlook.pst.
If you see that the repair tool has fixed some problems with the PST file, then you are probably in luck and autocomplete should work fine again, especially if it was reset every time you closed and opened Outlook.
The second way – import NK2 files
All versions of Outlook prior to 2010 saved this name / email address in a file with an NK2 extension. Outlook 2010 stores it differently, so you need to import this file if you are trying to get offer data from an older version of Outlook in Outlook 2010.
Check out the Microsoft KB article above on how to do this. You can download their FixIT program and just select the NK2 file and it will do the rest for you. If you want to do it yourself, you can find the file in the following location for Outlook 2003/2007 running Windows 2000 or XP:
C: Documents and Settings Username Application Data Microsoft Outlook
For Outlook 2003/2007 running Windows Vista or 7:
C: Users Username AppData Roaming Microsoft Outlook
Now, to import it into Outlook 2010, you need to make sure the NK2 file is in this directory:
C: Users username AppData Roaming
Finally, click the Start button, type Run, and in the Open dialog box, type the following command:
outlook.exe / importnk2
This should import the name cache from an older version of Outlook into Outlook 2010.
Method 3 – empty the auto-complete cache
In some cases, in order for this to work again in Outlook, you may need to clear the autocomplete cache. If everything is already deleted, it doesn’t matter, but it should help with the problem of repeatedly flushing the cache.
To clear your cache, go to File and click Options. Then click on “Mail” and scroll down to the “Send Mail” section.
Click the Clear AutoComplete List button. It’s also a good idea to deselect the Use AutoComplete List checkbox to suggest names as you type in the To, Cc, and Bcc fields. Exit Outlook and check the box again. Try entering multiple email addresses, then exit Outlook and reopen it and check if the names are still there.
Method 4 – Rename RoamCache
You can also get rid of the current cache completely and start from scratch, which might be the only way to fix the problem. You just need to rename the RoamCache folder to something else and Outlook will create a new one when you start the program again.
For Windows Vista and 7:
C: Users Username AppData Local Microsoft Outlook RoamCache
For Windows 2000 and XP:
C: Documents and Settings Username Local Settings Application Data Microsoft Outlook RoamCache
Fifth method – editing the NK2 file
Even though Outlook 2010/2013/2016 doesn’t have a specific NK2 file, they still store information in a file, but with a different name. File name:
And it’s located here:
C: Users Username AppData Local Microsoft Outlook RoamCache
If you are using Windows XP with Outlook, it is located here:
C: Documents and Settings Username Local Settings Application Data Microsoft Outlook RoamCache .
In Method 4, we renamed this RoamCache folder, but this deletes everything and forces you to start from scratch. If you just had this problem, you may be able to recover some of the suggested names by opening this Stream.dat file with a program called NK2Edit:
The first thing you can try is to simply open the .dat file with NK2Edit and then close it. When doing this, make sure Outlook is closed. Then open Outlook and see if that fixed the problem. Note that this program will automatically detect if you have Outlook installed and will download the cache file for you if it is stored in the default folder. You should immediately see the autocomplete list:
If it doesn’t open or you can’t open it manually, then you need to create a new cache file and replace the current stream.dat file. You can do this by opening NK2Edit and choosing File – New .NK2 File.
Then go to Actions and select Add Address Book Entries.
Now select the contact you want to use to create a new NK2 file. You don’t have to select all contacts if you don’t want to. You can also click the dropdown and click Suggested Contacts and see if there is anything there. If not, just select Contacts and then Control and click to select individual contacts.
Now execute the “File – Save As” command, navigate to the location of the current cache file (stream_autocomplete) and change the “Save As” type to .dat instead of NK2.
For the filename, simply select the current file you will be replacing. This is it! It’s a long process, but it works! And now you know how to completely fix and edit the autocomplete list yourself if you want!
You can also get a lot more information about Outlook AutoComplete on the Microsoft support website. If you’re still having problems or don’t understand something, leave a comment here and I’ll try to help! Enjoy!