| idc | Internet Database Connector |
| iddx | Adobe InDesign Static Defaults File |
| idg | Majax Configuration |
| idi | DB/TextWorks Last-used Settings |
| idp | IBM PComm Interchange Document Profile |
| idq | Internet Data Query File |
| iea | Image Eye Adjustment Data |
| iem | Internet Explorer Maintenance Extension |
| if2 | Intel Rapid Start Driver Setup Configuration |
| ifb | Siebel EIM Interface Configuration |
| igg | SuiteProfiler Color Map |
| igpi | Intel HD Graphics Profile |
| iip | ThinAnywhere Configuration |
| ikf | INTUS Terminal Keyboard Settings |
| ikmp | IK Sampletank Module Presets |
| ilc | Xpert.ivy Launch Control File |
| imo | iMON Manager Configuration |
| import | Godot Engine Import Settings Data |
| ini | Initialization File |
| ini-dist | PHP Distribution Default Settings Data |
| ins | Microsoft Windows Internet Settings File |
| inss | Mac OS X Setup Assistant ISP Info Data |
| interp | Gimp Interpreter Definition File |
| inz | Datalogic Lighter Configuration |
| ipcc | iPhone Carrier Bundle |
| ipk | iPack Configuration File |
| ipu | Vocaltec Internet Phone User Data |
| ir | Crestron BPC-HPLIR IR File |
| irbrc | Interactive Ruby Console Configuration Data |
| iros | Adobe Photoshop Save For Web Tool Settings |