it's a really horrible dream!
One morning , afeter i open my computer, i found that allmy asp.net web application could not run again!
I searched the problem with google, but nothing is valuable.
The following method is at least useful to me, I hope u are also lucky!
First of all, update your antivirus software and make a full scan on your computer. I guess the cause of the problem is that some hacker has entered in my computer and made some change in my account and security settings, so the sensitive asp.net found it and then stopped working.
After u are sure no viruse is in your computer, u can follow the steps below.
1. run"aspnet_regiis -ua" in the cmd. u can start the cmd from the vs.net tools in the start menu, otherwise u need type the full path.
2. remove the aspnet account from your computer
3. uninstall iis
4. restart your computer
5. reinstall iis
6. run "aspnet_regiss -i" in the cmd
7. add vs_developers group to iis operators (u can operation in iis)
8. open the file "machine.config" which is in "C:\WINNT\Microsoft.NET\Framework\v1.1.xxxx\CONFIG", then find and replace
userName="machine"
with
userName="SYSTEM"
9. restart your computer and pray silently
I can't promise u anything, but i will prayfor u.