There is a problem with the proxy server’s security certificate

Recently I was working on a project and I came across with the below error message for roaming users. I was not able to configure outlook profile remotely. While configuring the profile you will get this below error message.


Figure : 1 Error Message
The problem occurs when you have Exchange Certificates from an Active Directory Certificate Authority.

Solution: You have to download the certificate from Exchange and Install them manually on each client machines who are not a domain joined users.

To install Certificate on client machines follow the below steps.

Copy the certificates which you have exported from Exchange Server to the client machine.

From Client Machine

Go to Start > Run > type MMC > and then Enter


Figure 2 : MMC Console


Figure 3 : Options to select

In figure 3 Select Add/Remove Snap-in…


Figure 4 : Steps and Options to Select


Figure 5 : Import Certificate on Local Computer


Figure 6 : Import Wizard


Figure 7 : Browse and Select the Cert


Figure 8 : Selecting Certificate Store

Click Finish in the final window.

Repeat the steps from 5 though 8 forTrusted Root Certificate and for Intermediate Certificate Authority.

Post which you should be able to configure outlook profile from a remote location.

Hope this information was useful.




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6 Responses to There is a problem with the proxy server’s security certificate

  1. Gulab Prasad says:

    So, it’s a workaround and not the resolution! How would I fix it, if I have large number of clients?

  2. Sunder says:

    If they are domain joined users then Group Policy will help you.
    If they are not domain joined then only manual process.

  3. Pooriya says:

    I got the same error and used the solution which solved my problem. After this I acquired a third party public certificate and assigned my IIS,SMTP,IMAP,PoP to the third party certificate. After this my clients got disconnected from exchange, I received a similar error. it say “There is a problem with the proxy server’s security certificate. The name on the security certificate is invalid or does not match the name of the target site “sitename”. Outlook is unable to connect to the proxy server. (Error Code 10)”. Could you please assist me with this? Thank you for your time and concern.


  4. Sunder Rajan says:

    Before acquiring new certificate. What certificates you were using? Your comments does says.
    “I got the same error and used the solution which solved my problem”. Could you please be more specific.

  5. Spamhater007 says:

    I ran into this similar error, except the spelling of the domain name had a typo graphical error – two letters were reversed in the external hostname field (certificate was correct). instead of

    Ran Get-OutlookAnywhere | fl server,name,*hostname,ssl*,*auth* to find which server it was on, corrected the name. restarted services, but client still reported the same error. Had to remove client outlook profile and rebuild, repair did not correct.

  6. mulex says:

    where do i get Cert during importing