The current identity (NT AUTHORITY\NETWORK SERVICE) does not have write access
You get this error when default Network service does not have permissions on the IIS website.
Error looks like this.
This can be fixed by allowing access using aspnet_regiis - ga like this:
c:\WINDOWS\Microsoft.NET\Framework\v4.0.30319>aspnet_regiis -ga "NT Authority\Network Service"
Go to command prompt. Go to the respective directory and run the command. You should see Start granting command message.