How to Delete the Skype for Business (Lync) SIP Profile



I recently had a scenario, where clearing up the current Skype for Business Profile solved our problem, I our case the Skype for Business client had problems logging on and it was not related to network or DNS.

The desktop client of Skype for Business (or Lync 2010 / Lync 2013) cache a lot of information on the PC. This caching information is used when the client does e.g. signs-in. The cache is to minimize the bandwidth consumption of the Skype for Business (Lync) client, since it retrieves a lot of information from cache.

This cached information is stored in the users SIP Profile in a folder named sip_(SipURI of the user) located on a Windows computer in the following folder, depending of the client version:

  • Lync 2010: %UserProfile%\AppData\Local\Microsoft\Communicator\
  • Lync 2013: %UserProfile%\AppData\Local\Microsoft\Office\15.0\Lync
  • Skype for Business: %UserProfile%\AppData\Local\Microsoft\Office\16.0\Lync

If there are any issue with the cached files in the SIP profile, users might experience issue with desktop client such as:

  • Problems logging on (Check if network and DNS is okay first, though)
  • “User is not SIP enabled” errors
  • Unable to search the Global Address List
  • Contacts appear to be offline
  • Contacts are missing from the contact list
  • Contacts display “Presence Unknown”
  • Presence is not displayed in Outlook or SharePoint
  • “Skype for Business Server is Temporarily Unavailable” or “Lync Server is Temporarily Unavailable” errors

Additionally, it could be good practice to delete the SIP profile when switching to a new Skype for Business (Lync) platform as connection information can be cached.

To resolve the issues listed above, use the following guidance to delete the SIP profile for the affected user.

NOTE: Depending on the Windows Explorer settings, the SIP profile folder may be hidden, if you are unable to navigate to the path listed for your version of the Skype for Business or Lync client you will need to set Windows Explorer to Show Hidden Files and Directories prior to completing the steps below.

How to Delete the SIP Profile

  1. Close Skype for Business (SfB) or Lync completely by right-clicking the SfB / Lync icon in the Windows System Tray and selecting Exit.
  2. Open Windows Explorer and navigate to the folder that corresponds to the SfB / Lync client version that is installed
  • Lync 2010: %UserProfile%\AppData\Local\Microsoft\Communicator
  • Lync 2013: %UserProfile%\AppData\Local\Microsoft\Office\15.0\Lync
  • Skype for Business: %UserProfile%\AppData\Local\Microsoft\Office\16.0\Lync
  1. Delete the sip_username directory that matches the sip address of the user experiencing the issues.  This directory will be rebuilt when the SfB / Lync client is restarted the next time.
  2. Restart the computer
  3. Restart the Lync client

The SIP profile folder and cached information will be rebuilt, when the client starts again and the issues above should be resolved.

Hope this helps.

24 thoughts on “How to Delete the Skype for Business (Lync) SIP Profile”

  1. We had to rename our users in our company, going from [name] to [name] Now a majority of our users are listed in Skype for Business as “Presence Unknown.” I tried the fix above, but it didn’t seem to change anything. Do you have any other thoughts on what we might try?

  2. If I delete the SFB client user profile, will it delete all of the groups I have created?

  3. if the user is present as precent unkown and this actions still not helping try to check in the setting of the contact card and make sure that the im is set to the organization mail and not a phone number or somthing.
    it took me a lot of time to discover it but it work eventually.
    right click-see contact card-im

  4. Thanks a bunch for this Peter. I was hoping my ‘not SIP Enabled’ error would disappear after a few days, but when it didn’t your solution here worked perfectly.

  5. Hello, I really need some help as I work for a large company and the responses from the off shore help desk are pathetic or lack of a response.

    I keep getting the DNS KB

    System details:
    Windows 10 Anniversay Build 1607
    Office 365
    Skype for Business 16.0

    I have deleted the SIP and TRACING folders in USER_NAME\APPDATA\LOCAL\MICROSOFT\OFFICE\16.0
    I have used windows doctor to clean the registry. No result.
    I have rebuilt the windows guest and Skype works for a short period (few days) then has the issue again

    I am not the server admin I am an end user. I do not know how to create the SIP entries if I need to.

  6. Any way I can pull SIP account information so that I can use telephony separately from a regular standalone SIP client?

      • Hi Peter, I’d like to use the phone line from a standalone SIP client. Could be a softphone, physical, doesnt matter. I dont even want all the collab integration, just telephoning.

        The idea behind this is to be able to telephone without having to log in to skype, so I can call and be called but not bothered via IM.
        Also, if this is even posible, i have a physicall SIP phone that would love to use along with skype just for the good old feel of the hardware phone. =)

        My company provided a DID number along with skype so i’m not using just the integrated Voip, there must be a SIP gateway skype is trunking with!!

        Thank you

  7. Tks

    Other problem i see is user login in sfb meeting and after some time audio just disconnect.
    Check if there is no other user loged in sfb on the same computer and make logout.

  8. Peter,

    Here is my scenario:

    Large Company – 10,000 people
    Hybrid environment for most – office 2010, outlook 2010, Skype for Business 365
    Skype 365 connects to Login Server, Active Directory account is NOT locked
    Occasionally, Skype 365 does NOT connect to Global Address Book Server, this appears to be random
    User is able to connect to GAB Server with SIP address and Active Directory Password
    Shutting down Skype 365, del lync app folder, starting Skype will connect Skype to the GAB w\o prompting
    Skype 365, generally, breaks again after each PC restart
    Is this issue the result of a hybrid environment – people on office 2010 and SFB 2015 dont have this problem
    Is this something where the only fix is to always del the lync app folder b4 starting Skype 365?
    Your comments are appreciated.

  9. Here is how I fixed it for one of my End users:
    Pull up contact card for “presence unknown” person, edit, link contact, select correct email address from outlook and click “ok”, it merged the correct email address to skype and deleted the old one. My end user’s issue occurred when the person who was presence unknown had their name changed in A/D and the other person’s skype didn’t update over correctly causing the “presence unknown” issue.

  10. I ran across this at my last company and the presence issue was related to a Shared Microsoft Service that Lync Uses along with other non Microsoft applications. That particular software had something to do with Five9 call center software using the shared service. …Don’t recall which one. We were relegated to users of that software living with the problem.

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