Can not access Links with home internet Wireless Router Problems.

[iGuest 3]

Can not access Links with home internetWireless Router Problems.

I can access internet with all computers in my house.

I have a web mail I can access through all internet access except  when connected to my house AT&T Universe DSL internet.  I have tried to access this web link with my house AT&T Universe DSL internet with three different computers with no luck.  I can take each of these computers and connect to another internet  with no problem accessing the web mail. 

I was able to access this web mail link through my home AT&T Universe DSL internet last month; however this month I am not able to access though the same AT&T Universe DSL  home internet. 

Could  the trouble be with my AT&T Universe Router?

 

-question by Suan Hughes