403 Forbidden
Forbidden You don't have permission to access /_vti_bin/_vti_aut/author.exe on this server. Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.
I recently had this error and thought I would pass along the solution that worked in my case.
I noticed that the error occurred when attempting to publish a specific file (in my case a jpg image). I suspected the file was somehow corrupted, so I opened it in a photo editor and re-saved it. This fixed the file and eliminated the error message, allowing the publishing to proceed.
In my case I had to fix several corrupted files one by one.