How-To Geek
Clear the Auto-Complete Email Address Cache in Outlook
Outlook 2003 has an automatic completion for any email address that you try to type into the To or CC fields. This feature does not pull from the contacts or address book, because you may have tried to email somebody that wasn’t in your contact list, and it will still add that to the auto complete list.
The problem comes in when you put in a bad address, and then every time you go to type in the email address, the incorrect one appears in the auto complete list.
To fix this problem, there are two ways around this. The easiest way is this:
- Start typing in the address that shows up incorrectly.
- Hit the Down arrow key to select the auto completed address.
- Hit the Delete key to delete the auto complete address
The other way is by opening the profile folder and deleting the .nk2 file.
- Open up windows explorer, and paste the following into the address bar:
%APPDATA%\Microsoft\Outlook
- Delete the Outlook.NK2 file that you find in this folder.
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Comments (83)
Programmer by day, geek by night, The Geek, also known as Lowell Heddings, spends all his free time bringing you fresh geekery on a daily basis. You can follow him on Google+ if you'd like.
- Published 12/6/06




Thank you!
Thank you for this fix but i have an issue, we lost our exchange and had to rebuild it from scratch. now when we recreated the email accounts we ended up having to manually input all the special SMTP address. The issue here was a lot of the old ones where set to a 8 characters username@domain.com (first letter of the first name followed by 7 characters of the last name), but this time around we just used the full last name. Now it only was a issue for people who’s her last name was longer than 7 characters and because the user all had the old address in there cache it caused a lot of issue for me as the technician.
my question is i need to clear the whole company’s cache, so im thinking of putting that command line into the login script,
/q “%APPDATA%\Microsoft\outlook\*.NK2″
would this work? is there are other way?
Hi,
I have Microsoft Outlook 2000.
I am trying to setup the autocomplete in the email box. When i put in an email address I would like it to automatically go thru the address book and autocomplete the email address.
At the moment it is autocompleting. It is expecting me to type in the complete address. Can you please tell me where the option for autocomplete is in Outlook 2000.
Thanks
Hi dude,
This is a simple but great tip.
Thanks
Raghav
thanks for that
Thank you very much, it’s very helpfule article.
Ditto. This was driving me crazy before and I had no idea how to resolve it.
Hi, please please help. I had hundreds of email entries on my autocomplete option for Outlook. However, just now, all the sudden, none of email addresses are autocompleting and it appears they are all missing or gone, but I did not do anything out of the normal. How do I recover these? Btw..I do use ACT if this helps. THANKS
sometimes Outlook 2003 Auto complete is being cleared itself !!!
i want to prevent that in the future
plz help me
thanks,
This is great. I recently moved a bunch of users from Exchange 5.5 to Exchange 2003 and I was having a lot of problems with people sending to the old address (SMTP was the same but x400/x500 is different which is what matters to Exchange with local addresses) and this helped me greatly.
Thanks,
Bob Stone
Hi,
I have Microsoft Outlook 2000.
I am trying to setup the autocomplete in the email box. When i put in an email address I would like it to automatically go thru the address book and autocomplete the email address.
At the moment it is autocompleting. It is expecting me to type in the complete address. Can you please tell me where the option for autocomplete is in Outlook 2000.
Thanks
chandrasekhar
Hi Aaron Aiken,
I too faced the problem. Check the files at “%APPDATA%\Microsoft\Outlook” in your system. Maybe, you can get some clues from there. If you get then please let me know.
– Prashanth DN Kannadiga
prash_dn@yahoo.com
**** at your own risk ****
For Outlook 2000:
Open up windows explorer, and paste the following into the address bar:
%APPDATA%\Microsoft\Outlook
rename the file ‘Microsoft Outlook Internet Settings.NICK’
to ‘Microsoft Outlook Internet Settings.NICK.bak’
kind regards
John
Thanx a bunch,
Jim
Autocomplete works in my Outlook 2003 but does not carry over to subsequent sessions i.e when I log off and back on to my system, I lose all my autocomplete data. I didn’t have this issue with Outlook 2000.
Thanks.
I wrote a batch file that will clear the MRU files and it works on XP.
@ECHO OFF
@TITLE Clear MRU from Outlook
@COLOR 1F
SETLOCAL
:START
CLS
ECHO É����������������������������������������������������������������������������»
ECHO º º
ECHO º º
ECHO º This script will will clear Most Recently Used lists from your º
ECHO º Outlook files. º
ECHO º º
ECHO º º
ECHO È����������������������������������������������������������������������������¼
ECHO.
ECHO.
ECHO 1. Clear Most Recently Used from Outlook.
ECHO 0. Do nothing and exit.
ECHO.
set choice=
set /p choice= Type 1 or 0 and hit ENTER :
if not ‘%choice%’==” set choice=%choice:~0,1%
if ‘%choice%’==’1′ goto DEL
if ‘%choice%’==’0′ goto END
ECHO “%choice%” is not valid please try again
ECHO.
goto start
:DEL
ECHO Y | DEL “%APPDATA%\Microsoft\outlook\*.NK2″
CLS
ECHO É����������������������������������������������������������������������������»
ECHO º º
ECHO º º
ECHO º Outlook’s Most Recently Used lists cleared successfully. º
ECHO º º
ECHO º º
ECHO È����������������������������������������������������������������������������¼
ECHO.
Pause
:END
Sorry, the comment formatting messed up the formatting of the fancy boxes. It took out all the extra spaces.
Bob, I wasn’t sure if the above was a response to my issue or a previous one.
Not really a response to anything. I just got a batch file to work and decided to share here is all
Thanks so much!! This was a MAJOR help =)
Hi I’m also having the same issue as Ben
“Autocomplete works in my Outlook 2003 but does not carry over to subsequent sessions i.e when I log off and back on to my system, I lose all my autocomplete data. I didn’t have this issue with Outlook 2000″
How do I stop outlook from clearing the cache everytime I log off?
Cheers
Gavin
Thank you for the stright foward simple answer.
for outlook2003
copy %APPDATA%\Microsoft\Outlook and paste in address bar
then copy the file outlook.nk2 in a safe place
when u found that ur cashe has been gone copy the file again to the location %APPDATA%\Microsoft\Outlook
and reopen ur outlook
its a temporary solution
Can clear all errors from our outlook that dosen’t work because it slows our new yahoo email beta donwn because now a error shows up thankyou.
Thank you…a real grey-hair fixer!
Have a client with the same problem- open outlook and the nickname file works for the day, close outlook and reopen – it does not work. I have removed the NK2 file already to let it make new – but still does not save. Running exchange 2003/Outlook 2003.
I have Office 2008. It does not seem like there is a file with the extension .nk2. There are a Outlook Data File, SRS, and an XML all with Outlook as the title. Does any one know how to clear the address cache in the new version?
In Outlook 2003, the ‘NK2 delete solution’ will work as described.
If at some point you have unchecked the “Suggest names when completing the To, CC and BBC fields” under Options/Preferences/E-mail Options/Advanced Email Options then a new NK2 file will not be generated when your Outlook session is closed – meaning it will not carry the cache forward to you next Outlook session
Hi. I don’t suppose you can help me out. I have a daughter with a learning disability I am trying to set msn on auto complete for her email. It seeems to fo the rest when she searches but can’t do this for email addresses. I checked interent explorer – content and all the boxes are ticked. Is there anything else I can do.
Thanks buddy…the tip is really helpful. I have been struggling hard from past few days to get the cached entry deleted. After going through your site, i could do it easily and quickly.
Nobody answered Dave, Apr22’08. I have the same problem. Any suggestions?
@ Ed
Alvin gave the correct solution for 2003 on May 14. I removed 2008 and went back to 2003, but there should be a similar option but you’ll have to do the work of looking for it.
@ chandrasekhar
Outlook 2003 in Tools | Options | Preferences tab | E-Mail Options | Advanced E-mail options there is a check box for “Automatic name checking”
@ everyone
nk2view works to delete only one name without deleting the entire nickname file (Google it). I’m sure there are other tools out there for editing them also.
You Rock! I spent 2 hours trying to figure out how to get rid of obsolete addresses out the drop down lists that appear when you type the first letter in the TO box. THANK YOU Now maybe I won’t find myself sending mail to obsolete addresses anymore.
Thank you very much !!! This problem has bothered me for years, because every time I wanted to mail my brother an unknown person turned up.
I wish all major problems could be fixed so easily.
Good – tip. So simple and so useful.
My problem is a little strange. with autocomplete on, I entered “Murray” and then “Check Names”. The name that came up was Greg, but who I wanted was Patrick. So I did the easy thing – started to put in “mur”, get the name list, arrow down and delete “Greg”. Ok – now when I type in “mur” I don’t get Greg but I also don’t get Patrick even though he is in my Contacts directory. Also, if I type in “murray” and hit “Check Names” Greg still comes up. And he is the only name presented so I can’t scroll down and delete him. What should I do?
Cathy
Great tip…was sending mails to the wrong email many times. Now I deleted all the incorrect emails.
Thanks
..I have an issue with a client – have read through the above questions and no one seems to nail this one (forgive me if im wrong) –
My client complains that before now… if he types a name into the ‘to’ field in a new email…. it used to give him the auto complete box with many many names (even those that are not in his contacts (i.e previous recipients of even just one email)…. suddenly recently… he will only have a max. of about 6 names in the autocomplete….. and apparently only those that are in his contacts/address book or very recent recipients of emails… but not say someone he sent a mail to 3 months ago!…
I can find no rhyme or reason for this….
can anyone sugest a fix and or an explanation?!?
many thanks in advance..
Rob Nichols
that worked like a charm! thank you guys!!
Might be worth mentioning that if all you want to do is clear the list, open the .NK2 file in notepad, select all (CTRL-A) and delete and save the file.
Thanks for the tip and the Batch file.
Hats Off
Thank you – thank you – thank you!
(Did I say thank you?)
how to check recently viewed messages in outlook 2003.
Thank you!! I have been struggling with this issue for years!
Simple and very easy. It`s working fine thanks a lot
FANTASTIC! I have spent many frustrating hours trying to figure out how to get rid of obsolete addresses out of the drop down lists that appear when you type the first letter in the TO box. THANK YOU i have now got rid of a name i never want to see again.
Auto complete is taking loooooong time to fill in the email address. Takes more than 15 seconds for an address to appear.??
MS Office 2007
Os:Windows Xp
Great tip. Still valid in Outlook 2007.
Dude, this saved me so much hassle today! Thanks!
Thanks it worked perfectly first time and for Outlook 2007. Simple solution when you know.
Very very useful and accurate information
Thanks you so much Dude!
Venkat
Thanks Mr Geek. You’re my hero.
I searched for a solution for this about 5 years back and found nothing!
I would often copy across my *.pst to my laptop and it would have everything I wanted…except the non-contact list auto-complete feature.
Problem now resolved
Thank you
Perfect, thanks!
Really thanks!
Hello All, The following is for anyone trying to reverse the process above – Restore lost addresses from the To field in Microsoft Outlook.
I stumbled upon this because I had to delete and create a new mail profile for one of our users due to a certificate error. By deleting and creating the mail profile, it fixed the certificate problem, but our user then lost his list of historic addresses in the “To” field. In this particular situation the old .NK2 file, along with the .SRS and .XML files still remained in the C:\Documents and Settings\Username\Application Data\Microsoft\Outlook folder. I took copies of the new NK2, SRS and XML files (in case there was a problem and I could restore them), then renamed all three of the old files to the new profile name. Please note, that before the certificate error, the users profile was named differently to the new one I created but I don’t know if this will make a difference in whether the old profile config files are retained in this folder.
If that wasn’t clear enough, hopefully this is more simple to understand. Outlook should be closed before doing any of this.
- Mail “Profile1″ was corrupt with certicate error
- Deleted “Profile1″ and created “Profile2″ for the same user (Control Panel – Mail – Show Profiles)
- This fixed the certificate problem but also deleted all of historic addresses in the “To” field of outlook
- Open C:\Documents and Settings\Username\Application Data\Microsoft\Outlook
- Created backup copies of “Profile2.NK2″, “Profile2.SRS” and “Profile2.XML”
- Renamed “Profile1.NK2″ to “Profile2.NK2″ and did the same for the SRS and XML files.
- Load Outlook and the historic addresses should be restored.
That was so. easy.
I went looking for the steps for removing a name from my autocomplete assuming that I would need to purge the entire cache. To find that removing a name was as simple as hitting the delete key reminded me that sometimes complex problems really do have simple solutions.
Thank you!
Thanks for the tip.
Hats Off :0
BIZTALK & SHARE POINT DEVELOPER
Thanks for sharing
Thanks!
Sweet relief!
Sweet Moses, that was helpful.
You’re a life saver ! Deleting the .nk2 file worked perfectly for me.
Thank you !!!!
This is an excelent solution I was looking for, thanks for sharing!!
Pura Vida!!
MCA.
I have Windows 7 and Office 2003 including Microsoft Outlook 2003. Problems:
- I can’t delete Oulook.nk2 (read-only not marked) from AppData-Roaming-Microsoft-Outlook.
- The addresses are not kept in the autocomplete list; once I manage to delete unwanted addresses from the file but then the autocomplete list never worked normally.The addresses are kept only one session; after log-off the computer addresses introduced the day before, disappear.
We ran into an issue with outlook 2007. Auto complete list was slow retrieving and typing in the body was delayed. Deleted n2k file and Outlook was better. Copied all contracts into “To” list and canceled. This auto populates n2k file again; however, latency issues still occur and launching can take anywhere from 10 seconds to 2 minutes depending on the size of a users inbox and multiple pst files. running xp with 2 gigs memory. Any suggestions? We are also running a document management system.
02-09-011 05:37AM
What EXACTLY does the .nk2 file contain? Please don’t use techno babble if you can help it.
cool
@Barry … In Outlook, do you remember when you try sending a mail to someone, whom you’ve sent a mail earlier before ? Can you recollect that
in the compose new mail window, when you actually start typing a person’s
name, a small drop down appears which contains list of all those people or
email-ids that begin with the first few letters that you’ve typed. For e.g
you want to send it to Bob Smith, then all other Bob’s would be listed,
like Bob Jones, Bob Dole, Bob Brown, etc. THIS LIST COMES FROM THAT .NK2 FILE. Got it buddy. Hope I’ve not confused you. !!
Hi dear
My problem is that whenever i entering the email id or name which was already saved in outlook contact file it’s taking time aroun 10 to 20 seconds to auto display.
How to resolve this problem?
Suggest me.
Hi,
Please someone help me.
I want to make multiple selection in the drop down menu of the .NK2 (CACHE) contacts in the outlook.
(When I create a new mail, I click on the to address, and for example i press “a”, so all email id’s starting from “a” is listed. I want to select ALL of them at once. Is it POSSIBLE?
FYI, there is a brilliant NK2 editor from NirSoft – NK2Edit v1.76 available here – http://www.nirsoft.net/utils/outlook_nk2_edit.html
Been using it for a while and works great.
Thank you
Super thanks
helpful tips
Thanks so much – I just couldn’t get rid of older email addresses. This was very helpful. God bless.
Thank you sooooooo much. This was really giving me fits!!!
This doesn’t work for. It’s a work computer so I can’t touch the file.
I start typing the email then use the down arrow to select it and the delete key just erases the email fromt the to field. If I start typing the email again it’s still there.
Am I supposed to be doing this in the TO: field of a new message?
Thanks for the simple but excellent solution (press the down arrow and hit delete!)
Hey boys: I got an annoying problem that just is driving me nuts; when I am using Outlook and I type the letter ‘Q’ into a subject line, anywhere in any word, it shuts down my Outlook completely. It is so bad that I have to call the ‘Queen’ of England the ‘KWeen of England’; it is enough to make a gal lick her own titties!! Please, any suggestions?
Dude,
Frickin’ sweet! So simple. So basic. I’m programmer. I don’t know why we overlook the simplest solutions. Humbling.
:|
pasim u p india
MY Autocomplete does not work Outlook 2003. My client is XP professional but that should not matter. I have deleted the OUTLOOK1.NK2 and my settings are set to suggest names while completing To, CC, and bcc. Any suggestions