Portal Users "Sign In" Problem

[GucluSen]

Hi,

I have installed "Portal for ArcGIS".

"https://xxx-1.mydomain.com/portal/home" is the main page of my portal in our network.

And this server has named for web like this;

"https://xxx.mydomain.com/portal/home"

Now;

I have use our portal; "https://xxx.mydomain.com/portal/home"

But when I want to sign in the portal and press "SIGN IN" button,

"https://xxx.mydomain.com/portal/home/signin.html" page is not open and give this error:

***********************************************************************************************
The page isn't redirecting properly Firefox has detected that the server is redirecting the request for this address in a way that will never complete.
    This problem can sometimes be caused by disabling or refusing to accept cookies.
**********************************************************************************************

But I can use portaladmin login page like this;

"https://xxx.mydomain.com/portal/portaladmin"

What could be the problem to this stuation? Portal users can not log in using "Sign In" button. But "portaladmin" log in page is reachable.

Thanks,

Güçlü

[WilliamCraft]

This error can be caused by corrupted cookies, cookies that aren't sent, or cookies that are blocked.  It can also happen if you are requesting the Portal site from bad bookmarks.  Try clearing the local cache and the cookies from your browser and then re-requesting the Portal site. 

http://kb.mozillazine.org/The_page_is_not_redirecting_properly

If this does not resolve the problem...
Does this issue occur with other browsers such as IE, Chrome, Opera, or Safari? 
What happens if you disable all firewalls from the client and try again?

[GucluSen]

This error can be caused by corrupted cookies, cookies that aren't sent, or cookies that are blocked.  It can also happen if you are requesting the Portal site from bad bookmarks.  Try clearing the local cache and the cookies from your browser and then re-requesting the Portal site. 

http://kb.mozillazine.org/The_page_is_not_redirecting_properly

If this does not resolve the problem...
Does this issue occur with other browsers such as IE, Chrome, Opera, or Safari? 
What happens if you disable all firewalls from the client and try again?

Thanks William,

I have tried to these;

* Cleaning the local cache and cookies
* Using IE, Chrome and Firefox
* Close client firewall

and result is the same.

"https://xxx.mydomain.com/portal/home"
"https://xxx.mydomain.com/portal/portaladmin"

addresses are reachable but

"https://xxx.mydomain.com/portal/home/signin.html"

address can not be reached.

Could the problem be server side and about IIS properties?
IIS properties have set up automatically by the web adaptor installing operation.
(Portal version is 10.2.1)