Return of Reckoning

I get this error can i get some help how to fix it?
Error starting: System.UnauthorizedAccessException: Access to the path 'D:\Downloads\Warhammer Online - Age of Reckoning\WAR.exe' is denied.
at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
at System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost)
at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, FileOptions options, String msgPath, Boolean bFromProxy)
at System.IO.FileStream..ctor(String path, FileMode mode)
at RoRLauncher.Client.patchExe()
at RoRLauncher.Client.Handle(PacketIn packet)

It's not like this question isn't asked on a daily basis, but would you kindly...

READ THE MOST COMMON ISSUES AND SOLUTIONS

...as is directly above your post, right under the Forum Rules.

MAke sure your files arent set to read-Only