Macintosh
Overview
Uninstall the printer driver in Macintosh.
Procedure
1
Open [Printers & Scanners] screen.
[Printers & Scanners] screen is opened by clicking the Apple mark and selecting [System Preferences] from [Apple Menu].
2
Select the name of the printer you want to delete and click [-].
The selected printer is deleted.
3
Close [Printers & Scanners] screen.
4
Drag the below installed files from [Library] - [Printers] - [PPDs] - [Contents] - [Resources] in [Macintosh HD] and drop them in [Trash].
KOI100C-3J.ppd
KOI100C-3_.ppd
5
Delete any unnecessary files from [Library] - [Printers].
Drag the below files from [Library] - [Printers] - [GENERIC] and drop them in [Trash].
KOI100C-3_.ppd
KOI100C-3.plugin
KOI100C-3.icns
6
Click Move from the Finder menu. Hold down the option key and click [Library]. Drag the below files from [Preferences] and drop them in [Trash].
100C-3 Printer Driver x86_64 Preferences
The above files may now show up depending on the driver settings.
[User Name] is set to the account selected when login.
7
Restart your PC.
in the upper-right of a page, it turns into 
and is registered as a bookmark.