Tvheadend

Hello everyone,
I'm not getting crazy since I cannot find anything that works and therefore I hope you can help.
I own a sinology DS411Slim and installed the Tvheadend via the repository.
When I click on the Tvheadend icon it opens a window asking for name and password.

None of the name and password I know is working I tried : computer name password, sinology name password, forum password... can you help me to understand what is the name and password to use to enter the web page ?
Thanks in advance,