My webhost upgraded the server I was on recently, and I can no longer log into DNN. Its Version 4.9 (have another install, R5.1 that was fine after the upgrade). When I log in it just returns to the previous page. I have tried to google for a solution but have had no luck. Connected to the DB and looks ok. checked the web.config file and I can see the validation keys. Can someone please explain to me how the validation keys work? Would this be causing me problems? Also (one last q) how does one regenerate machine validation keys?

Thanks... Andy.

Thats right, no error message at all. It appears as if it has logged in, but then returns to the previous page. I had read up another problem similar to this that suggested that the Machine Validation Keys may not have been copied over, but I checked web.config and it is all there.

The upgrade was basically the web host replacing the hardware. I am not sure exactly how they did it, however I have another dnn website hosted on the same server and it works fine.

After posting this yesterday I decided to log into the database using visual studio as I dont have Management Studio installed. I checked the event table and it shows that host user was logging in, so I am not sure what is going on. I am starting to get desperate now, about to start looking at code!