| ldf | Microsoft SQL Server Transaction Log |
| ldfx | LogPlot LogDesign XML File |
| ldi | LDAP Data Interchange Format File |
| ldif | LDAP Data Interchange Format File |
| ldk | Larson Davis System 824 Firmware Authorization Data |
| ldl | Paradox Delivered Library |
| ldm | Sybase PowerDesigner Logical Data Model |
| ldp | Active Directory Exported LDAP Data |
| ldt | EULUMDAT File |
| ldt | Oracle Generic Loader Data File |
| led | AIBO LED File |
| lef | LEN Exchange Format File |
| lef | EnCase Logical Evidence Data |
| len | Esko PlatePrep Len File |
| leo | Leo Editor Outline Data |
| lepf | Little Endian Prebuilt Format File |
| les | Mklesson Lesson File |
| les | TurboWin LES Data |
| lesshst | Less History File |
| lex | Microsoft Office Custom Dictionary |
| lexe | SciTE Data |
| lfa | Life Forms Studio Motions Data |
| lfb | Laserfiche Briefcase |
| lfe | Laserfiche Shortcut |
| lfp | IPRO LFP Data |
| lfs | Samsung Android Phone LFS File |
| lfv | Labassert Functional View Library |
| lg1 | OptionVue Portfolio Manager LGN Backup |
| lg2 | OptionVue Portfolio Manager LGN Backup |
| lg3 | OptionVue Portfolio Manager LGN Backup |
