I am fairly new to DNN. my company asked me to upgrade to the newest verison of DNN. The first up grade went smooth and fine but the second one that housed all the important sites wouldnt not go past 0% during upgrade and got stuck in a loop. now all my company sites are down and if I dont get them back up I am fired. it really is that serious. I have the sites installed under the folder "dotnetnuke" the weird thing is 4 of the sites under that folder work but with no admin login. all other sites just get 404 error. Please I am begging anyone for help.

Thank you so much for your reply. I really do appreciate it. I added the back up folder back but it did not take, it still gives me the error. it looks like there is version mismatch. so dnn will not load at all. I replace the 3 files below in the bin folder and was able to get some of the sites back up but with no admin login into dnn. the other sites still wont come up. I was able to get buickdriveforyourstudents.com back up but the layout is all messed up.

System.Web.WebPages.Razor

System.Web.WebPages

System.Web.WebPages.Deployment