OR8-Rational-Rose-Oracle8-database-model-report
OR8-Rational-Rose-Oracle8-Database-Model-Report-IBM
ORA-Configuration-file-Oracle-7
ORA-Parameter-file-Oracle
ORB-Unknown-or-unassigned-file-extension
ORC-Script-Oracle-7
ORD-Bc45-Owl-file
ORDEREDTEST-Microsoft-Visual-Studio-ordered-test-file
ORD-OMAX-Routed-Data-File
ORD-Open-Reminder-database-file
ORE-3WayPack-The-Three-Mode-Company
ORE-Narbacular-Drop-Game-Content-DigiPen-Corporation
ORF-A-RAW-Image-File
ORF-Descent-3-Outrage-Room-Format
ORF-Olympus-Digital-Camera-Raw-Image-File
ORF-Olympus-digital-camera-RAW-image-Header
ORF-Olympus-Raw-File
ORG-Calendar-file-Lotus-Organizer
ORIG-Generic-original-file
ORIG-Gen-original-file
ORIGINAL-Netobjects-fusion-Components-Bbscomp-message-file
ORI-Need-for-Speed-Hot-Pursuit-2-File
ORI-Original-File
ORK-Warhammer-Mark-of-Chaos-game-archive
ORM-Ormetis-Workbench-File-Ormetis-S-A-S
ORMV-Ormetis-View-File-Ormetis-S-A-S
ORO-3WayPack-The-Three-Mode-Company
ORS-DSP-Group-TrueSpeech-Audio-format-file
ORT-COREX-orthographic-transcriptions-file
ORT-Rich-Text-Editor-Document
ORX-RadiantOne-VDS-Database-Schema
OS-2-archive-file-i-e-archives-keys-OS-2
OS-2-operating-system-file-type
OS3-OS-2-Warp-3-File
OS3-Os2warp3-file
OSAX-Mac-File-Type
OSB-Sega-Dreamcast-Sound-One-Shot-Bank-Sega-of-America-Inc
OSC-Formula-One-2001-Options-File
OSC-Fruitypro-Samples-Ss_-effects-file
OSC-OptionScope-worksheet-file
OSC-Remote-Installation-Services-Client-Installation-Wizard-File-Microsoft-Corporation
OSD-Directory-Opus-Configuration-File-GPSoftware
OSD-driver-file
OSD-Open-Software-Description-File-Microsoft-Corporation
OSD-OSD4-data-file
OSD-SoftGrid-program-description
OSDX-Windows-Search-Connector-Microsoft-Corporation
OSF-Descent-3-Sound-File-Outrage-Entertainment
OSF-Dist-Bin-file
OSF-Distribution-bin-file
TechTarget file types