Can I use old O2 router which I borrrowed from a friend with my new connection?

Hi,
I recently got a new o2 dsl connection but didn't order the router as my friend gave me one a couple of months ago I thought I could use that with my connection.

Whil3 initial configuration it detectes everything fine but it got stuck on "Zugangs-PIN" I entered the pin i got in email but its not working and says "pin is wrong" also when I try to skip the pin the connection is limited.

Is there anyway I can cofigure this and get the internet working? I don't have any previoua details of router.

I am using O2 HomeBox 6641.

Any help would be great.

Thanks & Regards.