| ifg | Samsung IFG Theme Package |
| igl | igLoader Plugin |
| ikm | Ideal Kitchen Monitor Backup Data |
| imscc | Canvas Course Export Package |
| incp | Adobe InCopy CS3 Package |
| indp | Adobe InDesign CS3 Package |
| inr | SAP BR Tools Incremental Backup Archive |
| ipd | BlackBerry Phone Backup |
| ipg | iPod Game Package |
| ipk | Zaurus Install Package |
| ipsw | iPhone / iPod Software Update |
| iqb | AmeriCalc Backup |
| iqzip | Inquisit Script Package |
| irz | iROS Application Package |
| isdocx | ISDOC Archive |
| ispac | Microsoft SQL Server Deployment Packet |
| ita | IconTweaker Theme Archive |
| itmsp | iTunes Store Package |
| iwa | iWork Archive File |
| iwzip | Incomedia Website X5 Project Archive |
| ixn | Mentor Graphics Service Pack Archive |
| ize | IZArc Encrypted Archive |
| j01 | Akeeba Secured Backup Archive |
| j01 | Akeeba Multi-part Backup Archive |
| j02 | Akeeba Multi-part Backup Archive |
| j02 | Akeeba Secured Backup Archive |
| j03 | Akeeba Secured Backup Archive |
| j03 | Akeeba Multi-part Backup Archive |
| j04 | Akeeba Secured Backup Archive |
| j04 | Akeeba Multi-part Backup Archive |
| j05 | Akeeba Secured Backup Archive |
| j05 | Akeeba Multi-part Backup Archive |
| jar | Java Archive |
| jbackup | The Journal Backup Archive |
| jdb | Symantec Endpoint Protection Update |