Quote
Here's the exact syntax I'm putting in at the command prompt:
"C:\Program Files\MySQL\MySQL Server 5.6\bin\mysqld.exe" --console --defaults-file="C:\ProgramData\MySQL\MySQL Server 5.6\my.ini"
When you install MySQL under Windows, it us usually installed as a
Windows Service, which means it will run with
highly elevated permissions. In short, it can write
anything it wants pretty much
anywhere it wants.
When you run mysqld
manually, you are running under
your user account, which has far less permissions and, almost certainly, won't be able to write to the same places as the installed, Service-ised, MySQL instance.
Try starting mysqld from an elevated ("Run as Administrator") console window and see if you get any further.
You say you checked for the files being "read-only"; you didn't mention checking the Security properties on the file(s) and directories. It's possible (nay, likely) that your account won't be able to write to those files; whether you
need this or not is debatable. They're managed by MySQL itself, so "users" shouldn't need any access to them at all.
Regards, Phill W.