Glad you solved it.
I also had this issue previously; it was caused by an I/O error related to my disk and character folder, which might not have had anything to do with ffxiv.

• My solution was to run a `CHKDSK C:\ /F /R /offlinescanandfix` which required a reboot to run -- this resolved the I/O error.

• An alternative solution is to rename the character folder in `%USERPROFILE%\Documents\My Games\FINAL FANTASY XIV - A Realm Reborn\` to something else, and then re-setup all your hud and macros and stuff -- or download a copy from the server if you previously backed up your settings.

○○ The basic issue was that the game couldn't read/write some part of the character folder for some reason.