Down load latest upgrade version of DNN 5.1 form dotentnuke.com.....1]Open the web.config of new 5.1 2]Chnage the both connection string form the old website web.config to new website web.config3]chanage the machine key from old web.config to new web.config4]Change object qulifier of old web.config to new web.config..Save new web.config properly....Copy all the upgrade version folder and paste on the root folder of old site...It automaticaly upgrade the site without any data loss.....Kishor Pawar.Pune