| ium | infoUSA Network Meter file |
| iup | Fritz Update |
| iut | SPaCIoS Tool IUT Definition |
| ivc | iView MediaPro Catalogue |
| ivd | Bitdefender Antivirus Incremental Database |
| ivex | Worldviz Vizard Encrypted Scene Data |
| ivl | ILOG JViews Map Data |
| ivl | ISIS Volume Output interval Data |
| ivm | Avaya Modular Messaging Voice Message |
| ivml | INDENICA Variability Modelling Language Data |
| ivn | Phase One Media Pro Notes Data |
| ivq | MSDN InfoViewer 5.0 Full-text Search Index |
| ivs | Aircrack-ng Initialization Vector Data |
| ivt | Beyond 20/20 Multi-dimensional Table |
| ivt | Concordance Inverted Full Text Database |
| ivw | i-Vocab World Array |
| ivwr | IntelliVIEW Offline Report Data |
| ivx | Beyond 20/20 Micro-data Extract File |
| ivy | Apache IVY Module Descriptor |
| iw | Chain Engineering Database |
| iw | IdleWild Screensaver File |
| iw2 | Information Workshop 2000 Data file |
| iwcf | Incomedia Website X5 Cell Style |
| iwl | Incomedia WebSite X5 License Data |
| iwm | AimTech IconAuthor File |
| iwnew | Autonomy Interwoven iwdeploy Server Received File |
| iwold | Autonomy Interwoven iwdeploy Server Received File |
| iwp | InfinityQS eSPC Data |
| iwt | Sunnysoft InterWrite Skin |
| iwtmp | OpenDeploy Temporary Data |
