| dnp | Neat Image Device Noise Profile |
| dns | Microsoft Windows DNS Server Database |
| dntu | DameWare NT Utilities Data |
| dnw | EMPOP DrawNetWork Data |
| do | Active-HDL DO Macro Data |
| do | Digital Line Graph Optional Vector Data |
| do | MicroSim PCBoard Autorouting Data |
| dock | DragThing Dock Data |
| dockerfile | Docker Settings Data |
| dockerignore | Docker Ignore File |
| dockpack | Stardock ObjectDock Package |
| docktheme | Stardock ObjectDock Theme |
| docmenx | Egis Encrypted DOCM Data |
| docmeta | Bukkit Information Data |
| docstore | Adobe Photoshop Lightroom Documentum Cache |
| doc_aq | Windows Essentials Codec Pack Data |
| dod | Autodesk Simulation Mechanical DDAM Displacement Results Data |
| dod | Progress Artix Data Services Data Model |
| dods | Distributed Oceanographic Data System Data |
| doe | Arena Model File |
| doi | BiRT Data Object Instance |
| dol | D-PAS Portfolio Manager Analysis Data |
| dol | Gamecube Executable DOL |
| dom | DIMPLOT Domain Definition |
| doms | SHERPA Domains Data |
| don | OpenOffice.org Log |
| don | PLS-CADD Lines and Annotation Data |
| done | Cygwin Postinstall Data |
| donotpresent | Time Machine Resource Fork Data |
| dop | DOpus Toolbar File |
| dop | DxO Optics Pro Sidecar File |
| dop | Voyetra Digital Orchestrator Pro Data |
| doq | Digital Orthophoto Quadrangle Data |
| doqq | Digital Orthophoto Quarter Quadrangle Data |
| dost | DoStudio Subtitle Format Data |
