BK9 file extension is for Timed backup file for document window 9 WordPerfect for Win
Similar to BK9
286 - Virtual device driver Windows standard mode2GR - VGA graphics driver Windows Video grabber
301 - Fax Super FAX 2000 - Fax-Mail 96
386 - Virtual device driver Windows 386 enhanced mode
3D2 - Atari Stereo CAD-3D 3D data file
3DM - QuickDraw 3D Metafile QuickDraw
3DMF - QuickDraw 3D Metafile QuickDraw
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