| u96 | EasyZip Temporary Data |
| ual | Entrust Auto-enrollment Server Unattended Login Credentials |
| uamodel | OPC-UA Model Data |
| uap | SIMATIC WinCC User Archive Export |
| ubd | UltraBac Data |
| ubj | Universal Binary JSON Data |
| ubjson | Universal Binary JSON Data |
| ubm | Apple iPhoto mtwain Install Data |
| ubox | Universe Sandbox Simulation Data |
| ubrl | Unicode Braille Document |
| ubrl6 | Unicode Braille 6-dots Document |
| ubs | Microsoft BugsLayer Data |
| ubu | UEFI BIOS Updater Data |
| ucae | Cellebrite Physical Analyzer Exported Data |
| ucc | National UCC Financing Statement Data |
| uccapilog | Windows Live Messenger UCC API Log |
| ucd | AVS Unstructured Cell Data |
| COOL 3D Plug-in Data |
| Prosa Diagram Data |
| uce | Microsoft Windows Unicode Extensions Data |
| ucf | WAsP User Corrections Data |
| Xilinx User Constraints File |
| uci | Samsung YP-P2 Theme Package |
| UFS Explorer Compressed Image |
| ucn | Unisys U-ACT Configurator Data |
| ucp | Xinapse Jim Uniformity Correction Parameters Data |
| ucr | MicroSim PCBoard Unrouted Nets Report Data |
| ucs | F5 User Configuration Set |
| uct | UC Browser Theme |
| ucv | Universal Converter Conversion Data |
| ud | OmniPage User Dictionary |
| uda | Zemax User-defined Aperture File |
| udb | Microsoft Dynamics AX User Database |
| PINO 3-Server Database |
| Ulead Burn.now Data |
| VBA32 Antivirus Signature Data |
| udc | Adobe InDesign User Dictionary |
| uddf | Universal Dive Data Format Data |
| udeb | Debian Package |
| udf | Microsoft Excel User Defined Function Data |
| Windows NT Uniqueness Database File |
| udg | uDraw Graph Data |
| udi | CorelDRAW Draw Script Textures Bitmap |
| Dazzle DVD Recorder Data |
| PANalytical Peak Data |
| udid | Android Unique Device Identifier Data |
| udl | ADONIS User Exported Data |
| EULANDA ERP System UDL Data |
| MDAC Universal Data Link |
| udo | Moray UDO 3D Data |
| udp | Corel VideoStudio Scene Information |
| uds | Generations Family Tree Document |
| Veritas NetBackup UNIX Domain Socket |
| udstate | Motorola Media Finder Data |
| udt | CX-Supervisor User Defined Text Data |
| Visilogic Utilities Data Table |
| wyUpdate Update Details File |
| udx | Philips Xenium Mobile Contacts |
| PI Expert Data |
| udz | UDA ConstructionSuite Data |
| ue | Uuencoded Data |
| ued | Universal Environmental Data |
| uef | Unified Emulator Format |
| uel | Tekla Structures Custom Components Data |
| uenc | UltraEdit Encrypted Text |
| ues | Ulead Photo Explorer SlideShow Data |
| uew | UltraEdit Word File |
| ufa | UltraMixer File Archive |
| ufc | SATURN Suite Data |
| ufd | UFED Physical Analyzer Data |
| ufdr | UFED Physical Analyzer Report Archive |
| ufdx | UFED Physical Analyzer Extraction Metadata |
| ufed | CelleBrite UFED Data |
| uff | BrainVoyager QX User Defined File Format |
| DataWave SciWorks Physiological Data |
| Scream Universal File Format Data |
| ufi | User Flash Image |
| ufl | Verity Server Custom Fields File |
| ufm | SATURN Suite Binary Matrix Data |
| ufo | Ellisys Visual USB Trace Data |
