Seam as if it is not the correct credentials, but I have changed my test user to the same password a number of times now:
[Mon Jul 27 22:55:28 2015] [error] [client 192.168.11.141] AuthExtern pwauth [/usr/lib/httpd/modules/pwauth]: Failed (255) for user benny
[Mon Jul 27 22:55:28 2015] [error] [client 192.168.11.141] user benny: authentication failure for "/test/addon/": Password Mismatch
exec of '/usr/lib/httpd/modules/pwauth' failed: (2) No such file or directory
[Mon Jul 27 22:55:29 2015] [error] [client 192.168.11.141] AuthExtern pwauth [/usr/lib/httpd/modules/pwauth]: Failed (255) for user benny
[Mon Jul 27 22:55:29 2015] [error] [client 192.168.11.141] user benny: authentication failure for "/test/addon/": Password Mismatch
exec of '/usr/lib/httpd/modules/pwauth' failed: (2) No such file or directory
[Mon Jul 27 22:55:29 2015] [error] [client 192.168.11.141] AuthExtern pwauth [/usr/lib/httpd/modules/pwauth]: Failed (255) for user benny
[Mon Jul 27 22:55:29 2015] [error] [client 192.168.11.141] user benny: authentication failure for "/test/addon/": Password Mismatch
exec of '/usr/lib/httpd/modules/pwauth' failed: (2) No such file or directory
[Mon Jul 27 22:58:22 2015] [error] [client 192.168.11.141] AuthExtern pwauth [/usr/lib/httpd/modules/pwauth]: Failed (255) for user benny, referer:
https://192.168.11.18/test/[Mon Jul 27 22:58:22 2015] [error] [client 192.168.11.141] user benny: authentication failure for "/test/addon/": Password Mismatch, referer:
https://192.168.11.18/test/exec of '/usr/lib/httpd/modules/pwauth' failed: (2) No such file or directory
[Mon Jul 27 22:58:22 2015] [error] [client 192.168.11.141] AuthExtern pwauth [/usr/lib/httpd/modules/pwauth]: Failed (255) for user benny, referer:
https://192.168.11.18/test/[Mon Jul 27 22:58:22 2015] [error] [client 192.168.11.141] user benny: authentication failure for "/test/addon/": Password Mismatch, referer:
https://192.168.11.18/test/