Help with D-Link DSL 6850U router.

[avitsur]

Hi, I have this old router which I would like to use as an access point. the thing is that this router was provided by the service provider many years ago. my problem is that when I try to enter the router in order to configure it, I'm getting a message that in order to protect from cyber hazards, I have to get an app that will allow me to enter. I don't want all the hassle and since it's a D-Link shelf product, I guess that there is a way to remove it and to bring it back to serve as a normally bought from store router. I found this article regarding it and since I'm no expert in networking - I will appreciate you opinion and help.
The D-LINK 6850U is a VDSL modem + router given by Israeli telecom provider Bezeq to customers of their high-speed VDSL plans (so-called Next Generation Network - NGN). The device seems to be custom made by D-Link specifically for Bezeq, and it arrives flashed with custom Bezeq firmware that includes many “features” such as open-by-default remote management ports (with default usernames and passwords!) and remote “management” backdoors that are very hard to shut off.

Note on TR-069 The modem/router has TR-069 enabled by default, the hidden URL to manage it is: http://10.0.0.138/_@tr69cfg.html (Where 10.0.0.138 is the default modem IP address). There is not explicit “disable” button there but changing the “ACS URL” (Bezeq server) to some internal IP address like 10.0.0.199 should do it.