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Outlook unable to connect to proxy server (error code 20)

Last Modified: 2020-06-11
This error has been poping up on all my computers that are using a ssl certificate created for our business for user to connect to our exchange server via https:// connection.

Cannot find anything online to help me with this.  Any help would be greatly appreciated.
Watch Question

If your exchange server is running on service pack 1, you may need to install service pack 2.


Ok i tried to update service pack and still produces an error 20  just after you login into outlook.  Did updates on server and on laptop with no noticeable results.
2 weeks ago it was fine and now i have an error 20.  since i did not create the SSL certificate i have no idea what to do next?

check this link and see if that helps http://support.microsoft.com/kb/923575


The info is resourceful, however i do not understand what i am to do.  Because i never dealt with ssl's other then installing them.  Would it be easier for me to create a new certficate or update the old.  This issue is causing huge problems for me.  When i look at the CERT it says it is set to expire in 2013.  So i have no clue how to trouble shoot this issue.
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xXWickedXx are you able to post the solution ( or pointers where to look) as I have exactly the same issue. Thanks


I never fixed it, by myself once i found out what the problem was,  I just got my network support cpant to create a new  SSL Certificate.
Had this issue, fixed it by following solution 3 on this site.

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