ADFS 2012 R2 Web Application Proxy Error

i'm getting following error in web application proxy admin event log can't figure out...any appreciated...i did try article no luck: http://technet.microsoft.com/en-us/library/dn584110.aspx

log name:      microsoft-windows-webapplicationproxy/admin
source:        microsoft-windows-webapplicationproxy
date:          9/17/2014 10:51:32 am
event id:      12021
task category: none
level:         error
keywords:     
user:          system
computer:      xxx
description:
web application proxy not bind ssl server certificate. error: cannot create file when file exists.
 (0x800700b7).
other configuration settings applied.

details:
certificate thumbprint: xxx
host name: xxx
event xml:
<event xmlns="http://schemas.microsoft.com/win/2004/08/events/event">
  <system>
    <provider name="microsoft-windows-webapplicationproxy" guid="{ea19457d-afb4-4b25-b526-da576cce3fe4}" />
    <eventid>12021</eventid>
    <version>0</version>
    <level>2</level>
    <task>0</task>
    <opcode>0</opcode>
    <keywords>0x8000000000000000</keywords>
    <timecreated systemtime="2014-09-17t14:51:32.966784500z" />
    <eventrecordid>161</eventrecordid>
    <correlation />
    <execution processid="4008" threadid="2884" />
    <channel>microsoft-windows-webapplicationproxy/admin</channel>
    <computer>xxx
    <security userid="s-1-5-18" />
  </system>
  <eventdata>
    <data name="error">cannot create file when file exists.
 (0x800700b7)</data>
    <data name="certthumbprint" xxx
    <data name="hostname">  xxx
  </eventdata>
</event>

thx

hi,

would please tell how did bind ssl certificate, correct one?

best regards,

amy

Windows Server  >  Windows Server 2012 Setup