Were you able to confirm the service is
                pointing at stunnel.conf and not stunnel.cfg maybe?
                
                > Date: Thu, 21 Aug 2014 16:43:16 -0700
                  > From: 
541401@gmail.com
                  > To: 
stunnel-users@stunnel.org
                  > Subject: [stunnel-users] Stunnel Windows Server
                  2008 R2
                  > 
                  > I have installed stunnel 5.03 on Windows Server
                  2008 R2 X64. When I 
                  > run it as an application it works perfectly. When
                  I install and run the 
                  > service, it starts but the start notice window,
                  title bar, says Stunnel 
                  > 5.03 win32 (not configured). It appears that the
                  stunnel service is not 
                  > reading the stunnel.conf.
                  > 
                  > If anyone has any suggestions how I can
                  successfully run stunnel as a 
                  > service, I would be very appreciative.
                  > 
                  > Thank you!
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