I use an ajax head request to check for a file. In most cases the file wouldn\'t exist and it would be nice to somehow prevent the 404 to show up in my debug console. Is th
No, unfortunately, you cannot.
404 errors are handled internally, you cannot suppress the error, not even with overwriting the error events in javascript or try-catching it.
You could write a serverscript to check if a certain file exists and call that one to check if the file exists before calling the file that might not exist.