The server can not find the requested page

i followed the instructions in the Docs for installing Elgg 1.6.1 and after what appeard to be a successful installation i created the first"admin" account and when trying to log in using it for first time i got a page containing this error msg:

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404 Not Found

The server can not find the requested page:

www.elgg.SiteName.com/~UserName/elgg/~UserName/elgg/action/login (port 443)

Please forward this error screen to www.elgg.SiteName.com's Web Master.


Apache/2.2.13 (Unix) mod_ssl/2.2.13 OpenSSL/0.9.8k DAV/2 mod_auth_passthrough/2.1 FrontPage/5.0.2.2635 Server at www.elgg.SiteName.com Port 443

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i replaced the real sitename,username  with the bold,italic,underlined words ...    now every time i try to access this subdomain i get the same msg and nothing more ... did i do somthing wrong .. what could be the cause of this?!