The link opens to a blank page for me in IE11, but opens to a sign in page using both Firefox and Chrome variant (Cent) browsers.

Maybe try this if possible.

I did see instructions on Google on how to get into your device by resetting everything at bootup.

https://www.google.com/search?as_q=reset+hp+stream+device&as_epq=&as_oq=&as_eq=&as_nlo=&as_nhi=&lr=&cr=&as_qdr=all&as_sitesearch=&as_occt=any&safe=images&as_filetype=&as_rights=

Jim.