I am having difficulty installing SDM v2.5 on a 1841 router. I have connectivity to the router, I have a login with privilege level 15. I am able to telnet to and login to the router fine. However, when I run the SDM setup, it gives the error message that SDM was unable to connect to the router.
I sniffed the network and SDM does telnet to the router, login, and then goes into and exits config mode, and that is it.
I do not have SSH enabled, but I'm not aware that that is necessary to install SDM.