I just had this same problem while I was following the "Basic Concepts" section of the RavenDB documentation, with the following output:
C:\RavenDB>Raven.Server.exe
Trying to grant rights for http.sys
runas netsh http add urlacl url=http://+:8080/ user="User-PC\User"
Failed to grant rights for listening to http, exit codes: (0 and 1)
A critical error occurred while starting the server. Please see the exception details bellow for more details:
System.InvalidOperationException: Could not write to location: C:\RavenDB\Data.
Make sure you have read/write permissions for this path. ---> Microsoft.Isam.Esent.Interop.EsentFileAccessDeniedException: Cannot access file, the file is locked or in use
<stack trace follows>
The issue was that the RavenDB installer had automatically started the RavenDB Server as a Windows Service, preventing the command-line Raven.Server.exe from being able to access the right directory. I just opened the Services control panel (Start menu -> services.msc) and stopped the RavenDB service. After that, starting Raven.Server.exe from the command line worked as demonstrated in the documentation.
Note that this is running on a Windows 7 x64 Professional machine in Development mode with RavenDB 2.5.2851.