System Files
The System Files category includes files related to Mac, Windows, and Linux operating systems. Some examples include system libraries, icons, themes, and device drivers. Files output by the system are also included in this category.
Common system file extensions include .DLL, .DRV, .SYS, and .CAB.
| Extension | File Type | Popularity |
|---|---|---|
| .DATABASE_UUID | Android Stale Thumbnails Identifier | 4.6 |
| .REG | Registry File | 4.4 |
| .AML | ACPI Machine Language File | 4.4 |
| .ADMX | Group Policy Administrative Template File | 4.4 |
| .CUR | Windows Cursor | 4.3 |
| .73U | TI-73 Explorer Operating System File | 4.3 |
| .REGTRANS-MS | Registry Transaction Log File | 4.3 |
| .ICNS | macOS Icon Resource File | 4.3 |
| .ICONPACKAGE | IconPackager Theme File | 4.3 |
| .CLB | COM+ Catalog File | 4.3 |
| .ANI | Windows Animated Cursor | 4.3 |
| .DLL | Dynamic Link Library | 4.3 |
| .DESKTHEMEPACK | Windows 8 Desktop Theme Pack File | 4.3 |
| .WDGT | Dashboard Widget | 4.3 |
| .SEARCHCONNECTOR-MS | Windows Search Connector File | 4.2 |
| .FTF | FlashTool Firmware File | 4.2 |
| .HTT | Hypertext Template | 4.2 |
| .VGA | VGA Display Driver | 4.2 |
| .HVE | Windows Registry Hive File | 4.2 |
| .ITEMDATA-MS | Windows 8 Start Screen Item Data File | 4.2 |
| .LNK | Windows Shortcut | 4.2 |
| .DMP | Windows Memory Dump | 4.2 |
| .NFO | System Information File | 4.2 |
| .DVD | DOS Device Driver | 4.2 |
| .MDMP | Windows Minidump | 4.2 |
| .PK2 | Silkroad Online Game Data File | 4.2 |
| .VX_ | Compressed Virtual Device Driver File | 4.2 |
| .RMT | Router Firmware File | 4.2 |
| .THEME | Microsoft Plus! Desktop Theme | 4.2 |
| .QVM | Q Virtual Machine | 4.2 |
| .RC1 | Samsung Mobile Device Firmware File | 4.2 |
| .PCK | System Center Configuration Manager Package File | 4.1 |
| .EBD | Windows EBD System File | 4.1 |
| .NT | Windows NT Startup File | 4.1 |
| .INF_LOC | Windows Driver Information Cache File | 4.1 |
| .SYS | Windows System File | 4.1 |
| .LIBRARY-MS | Windows Library Description File | 4.1 |
| .HIV | Windows Registry Hive File | 4.1 |
| .DESKLINK | Desktop Shortcut | 4.1 |
| .SCR | Windows Screensaver | 4.1 |
| .SFCACHE | ReadyBoost Cache File | 4.1 |
| .ASEC | Android Secure Application File | 4.1 |
| .ICO | Icon File | 4.1 |
| .PROP | Android Build Properties File | 4.1 |
| .MANIFEST | Windows Application Manifest File | 4.1 |
| .ELF | Executable and Linkable Format File | 4.0 |
| .ION | File Description File | 4.0 |
| .PAT | DiskStation Manager Installation File | 4.0 |
| .BIN | Router Firmware File | 4.0 |
| .000 | Indexing Service Data File | 4.0 |
| .MUI | Multilingual User Interface File | 4.0 |
| .EDJ | Enlightenment Theme File | 4.0 |
| .TIMER | Systemd Unit Configuration File | 4.0 |
| .FOTA | Firmware Over-the-Air File | 4.0 |
| .PWL | Windows Password List | 4.0 |
| .CGZ | Linux Drivers Archive | 4.0 |
| .FFX | Microsoft Find Fast Index | 4.0 |
| .MENU | macOS Menu Extra | 4.0 |
| .MAPIMAIL | Send To Mail Recipient | 4.0 |
| .FIRM | Boot9Strap 3DS Firmware File | 4.0 |
| .LOG1 | Windows Registry Hive Log File | 4.0 |
| .NLT | Windows Transliteration File | 4.0 |
| .PREFPANE | Mac OS X System Preference Pane | 4.0 |
| .LOCKFILE | Mac OS X PLIST Lock File | 4.0 |
| .ZONE.IDENTIFIER | Windows Zone Identifier File | 4.0 |
| .CI | Windows Content Indexer Catalog File | 4.0 |
| .SERVICE | Systemd Service Unit File | 4.0 |
| .ETL | Microsoft Event Trace Log File | 4.0 |
| .DAT | Windows Registry Hive File | 4.0 |
| .MSC | Microsoft Management Console Snap-in Control File | 4.0 |
| .CAB | Windows Cabinet File | 4.0 |
| .BASH_HISTORY | Bash History File | 4.0 |
| .ADM | Administrative Template File | 4.0 |
| .H1S | Windows Assistance Platform Help File | 3.9 |
| .FX | ReadyBoot Trace File | 3.9 |
| .WDF | Windows Driver Foundation File | 3.9 |
| .CPL | Windows Control Panel Item | 3.9 |
| .MOD | GRUB Module | 3.9 |
| .SDB | Custom Application Compatibility Database | 3.9 |
| .LFS | Samsung Phone params.lfs File | 3.9 |
| .MLC | Microsoft Language Interface Pack | 3.9 |
| .PIT | Samsung Phone Firmware File | 3.9 |
| .BASH_PROFILE | Bash Interactive Login Shell File | 3.9 |
| .MSSTYLES | Windows XP Style | 3.9 |
| .EFI | Extensible Firmware Interface File | 3.9 |
| .CM0013 | Samsung Smart TV Index File | 3.9 |
| .MOBILECONFIG | Apple Mobile Configuration File | 3.9 |
| .PNF | Precompiled INF File | 3.8 |
| .SYS | Motorola Driver File | 3.8 |
| .MTZ | MIUI Theme | 3.8 |
| .MBR | Master Boot Record File | 3.8 |
| .C32 | Syslinux COM32 Module | 3.8 |
| .POL | Windows Policy File | 3.8 |
| .HHK | HTML Help Index | 3.8 |
| .GROUP | Windows Contacts Group File | 3.8 |
| .WEBPNP | Web Point and Print File | 3.8 |
| .SBN | Cisco IP Phone Firmware File | 3.8 |
| .0 | Shared Library Link File | 3.8 |
| .208 | ASUS Notebook BIOS 208 Update File | 3.8 |
| .BIO | BIOS File | 3.8 |
| .DIAGCAB | Troubleshooting Pack Cabinet File | 3.8 |
| .BCD | Windows Boot Configuration Data File | 3.8 |
| .DRV | Device Driver | 3.8 |
| .BASHRC | Bash Non-Interactive Login Shell File | 3.8 |
| .DIT | Active Directory Information Tree File | 3.8 |
| .INS | Internet Naming Service File | 3.8 |
| .3FS | Puppy Linux Save State File | 3.8 |
| .DEV | Windows Device Driver File | 3.8 |
| .IMG3 | iPhone IMG3 File | 3.8 |
| .PLASMOID | Plasma Widget | 3.8 |
| .IOPLIST | Mac OS X IOPLIST File | 3.8 |
| .PDR | Windows Port Driver | 3.8 |
| .MSP | Windows Installer Patch | 3.7 |
| .DRPM | Delta RPM File | 3.7 |
| .AOS | ARCHOS PCtablet Firmware File | 3.7 |
| .PRF | Windows System File | 3.7 |
| .DTHUMB | Android Data Thumbnail | 3.7 |
| .SDT | Siemens Desktop Theme File | 3.7 |
| .SAVEDSEARCH | Spotlight Saved Search | 3.7 |
| .CANNEDSEARCH | Apple Predefined Search | 3.7 |
| .CHS | Windows Chinese Noise-Word List File | 3.7 |
| .PROFILE | Bash Shell Profile | 3.6 |
| .CNT | Help Contents File | 3.6 |
| .JOB | Windows Task Scheduler Job File | 3.6 |
| .NLS | Microsoft National Language Support File | 3.6 |
| .PPD | PostScript Printer Description File | 3.6 |
| .MBN | Multi Boot Image | 3.6 |
| .SBF | Android System File | 3.6 |
| .WPX | Printer Description File | 3.6 |
| .HDMP | Windows Heap Dump | 3.6 |
| .SQM | Service Quality Monitoring File | 3.6 |
| .CAT | Windows Catalog File | 3.6 |
| .VXD | Virtual Device Driver | 3.6 |
| .CRASH | Mac OS X Crash Log File | 3.6 |
| .BOM | Mac OS X Bill of Materials File | 3.6 |
| .MUI_CCCD5AE0 | Hid User Library | 3.6 |
| .LOG2 | Windows Registry Hive Log 2 File | 3.6 |
| .FPBF | Mac OS X Burn Folder | 3.6 |
| .IDX | Index File | 3.6 |
| .LST | GRUB Boot List File | 3.6 |
| .NB0 | Device Boot Loader Image | 3.6 |
| .8XU | TI-83 and TI-84 Plus Operating System File | 3.6 |
| .SHD | Windows Print Job Shadow File | 3.6 |
| .KEY | Security Key | 3.6 |
| .ADML | Group Policy Language-Specific Administrative Template | 3.6 |
| .HLP | Windows Help File | 3.5 |
| .GRP | Windows Program Manager Group | 3.5 |
| .CHG | Windows Net Logon File | 3.5 |
| .PANIC | Kernel Panic File | 3.5 |
| .SCHEMAS | GConf Schema Definition File | 3.5 |
| .SWP | Swap File | 3.5 |
| .CPQ | Compaq OEM Disc Configuration File | 3.5 |
| .SHSH | iPhone/iPod Touch SHSH Blob File | 3.5 |
| .DFU | iOS DFU File | 3.5 |
| .IME | Windows Input Method Editor File | 3.5 |
| .TDZ | Drobo Firmware File | 3.5 |
| .KS | Kickstart File | 3.5 |
| .386 | Windows Virtual Device Driver | 3.5 |
| .2FS | Puppy Linux Save State File | 3.5 |
| .KEXT | Mac OS X Kernel Extension | 3.5 |
| .FLG | Puppy Linux Partition Flag File | 3.4 |
| .PS2 | Microsoft Search Catalog Index File | 3.4 |
| .HHC | HTML Help Table of Contents | 3.4 |
| .CHK | Netgear Router Firmware File | 3.4 |
| .HCD | Samsung Android Firmware File | 3.4 |
| .KO | Linux Kernel Module File | 3.4 |
| .ODEX | Optimized Dalvik Executable | 3.4 |
| .WER | Windows Error Report | 3.4 |
| .ADV | Audio Driver File | 3.4 |
| .8CU | TI-84 Plus C Operating System File | 3.3 |
| .IM4P | IMG4 Payload File | 3.3 |
| .PRINTEREXPORT | Windows Printer Migration File | 3.3 |
| .PRO | TurboIntegrator Process Definition File | 3.3 |
| .CPI | Codepage Information File | 3.3 |
| .THA | Windows Thai Noise-Words List File | 3.3 |
| .ICL | Windows Icon Library File | 3.3 |
| .PROVISIONPROFILE | Apple Provision Profile | 3.3 |
| .DIMAX | DiMAX Firmware Image File | 3.3 |
| .PFX | PKCS #12 Certificate File | 3.3 |
| .NTFS | NTFS Partition File | 3.3 |
| .BMK | Help Bookmarks | 3.3 |
| .CHT | Windows Chinese Traditional Noise-Word List File | 3.3 |
| .METADATA_NEVER_INDEX | Spotlight Never Index File | 3.3 |
| .BLF | CLFS Base Log File | 3.3 |
| .NBH | ROM Update Utility Image File | 3.3 |
| .MI4 | Audio Player Firmware File | 3.3 |
| .TRX_DLL | Windows Startup File | 3.3 |
| .FFO | Find Fast Document Properties Cache | 3.3 |
| .MSSTYLE | Windows XP Unsigned Style | 3.3 |
| .ATAHD | ATA Hard Drive Flag File | 3.3 |
| .PRT | Printer Driver File | 3.2 |
| .PID | Creative Driver File | 3.2 |
| .XRM-MS | Microsoft Security Certificate | 3.2 |
| .SO.0 | Unix Shared Library File | 3.2 |
| .RUF | Samsung DVD and Blu-ray Player Firmware File | 3.2 |
| .STR | Windows Screensaver File | 3.2 |
| .CM0012 | Configuration Management File | 3.2 |
| .SAVER | Mac OS X Screen Saver | 3.2 |
| .CUSTOMDESTINATIONS-MS | Windows Jump List File | 3.2 |
| .BK2 | Windows Indexing Service Data File | 3.1 |
| .SPL | Windows Print Spool File | 3.1 |
| .MUM | Windows Vista Update Package | 3.1 |
| .THUMBNAILS | Android Thumbnails Folder | 3.1 |
| .CAP | ASUS BIOS Update File | 3.1 |
| .CPR | Windows Phone Display Settings File | 3.1 |
| .PS1 | Microsoft Indexing Service Data File | 3.1 |
| .EVTX | Windows 7 Event Log File | 3.1 |
| .KC | macOS Kernel Extension Boot File | 3.0 |
| .DOCK | Mac OS X Dock Extra | 3.0 |
| .CONFIGPROFILE | Apple Configuration Profile | 3.0 |
| .RFW | Rockchip Firmware File | 3.0 |
| .EFIRES | EFI Image File | 3.0 |
| .HSH | Windows Catalog Search Index File | 3.0 |
| .SIN | Sony Xperia Firmware File | 3.0 |
| .CMO | ASUS BIOS File | 3.0 |
| .BK1 | Windows Indexing Service File | 3.0 |
| .GMMP | WCS Gamut Map Model Profile | 3.0 |
| .ESCOPY | ES File Explorer File Manager Temporary File | 3.0 |
| .B84 | TI-84 Plus CE Bundle Image | 3.0 |
| .WGZ | S60 Web Runtime Widget Package | 3.0 |
| .0 | Android CA Digital Certificate | 3.0 |
| .DIC | Windows 10 Custom Spelling Dictionary | 3.0 |
| .SHSH2 | iOS SHSH Blob | 3.0 |
| .B83 | TI-83 Premium CE Bundle Image | 3.0 |
| .DLX | Renamed DLL File | 3.0 |
| .HPJ | Help Project File | 3.0 |
| .MUN | Windows System Resource Archive | 3.0 |
| .LPD | LPD Daemon Print Permissions File | 3.0 |
| .ME | Puppy Linux Partition Flag File | 3.0 |
| .IFW | INTUS Firmware File | 3.0 |
| .KDZ | LG Mobile Device Firmware | 3.0 |
| .DIAGPKG | Troubleshooting Pack File | 3.0 |
| .UCE | Windows UCE System File | 3.0 |
| .MEM | Parallels Desktop Memory Dump File | 3.0 |
| .XFB | Xserve RAID Firmware Binary File | 2.9 |
| .SCF | Windows Explorer Command | 2.9 |
| .GRL | Windows Update Status File | 2.9 |
| .SCAP | EFI Firmware File | 2.9 |
| .TRASHES | macOS USB Flash Drive Trash Folder | 2.8 |
| .FFA | Find Fast Status File | 2.8 |
| .MYDOCS | Send To My Documents | 2.8 |
| .FL1 | Lenovo BIOS Update File | 2.8 |
| .DEVICEMETADATA-MS | Device Metadata Package | 2.8 |
| .DYC | Xerox Printer Driver Configuration File | 2.8 |
| .KBD | Keyboard Layout Script | 2.8 |
| .PPM | Post Programmable Memory File | 2.7 |
| .AUTOMATICDESTINATIONS-MS | Windows Jump List File | 2.7 |
| .RC2 | Samsung Mobile Device Firmware File | 2.7 |
| .OZIP | OPPO Smartphone Firmware Update | 2.7 |
| .IDI | EVA Controller Event Log | 2.6 |
| .DSS | DCC Active Designer File | 2.6 |
| .SB | Slax Bundle | 2.6 |
| .BUD | Binary Printer Description File | 2.6 |
| .VGD | Generic CADD VGA Driver | 2.6 |
| .RCO | PlayStation Portable Resource File | 2.5 |
| .LOCALIZED | macOS Directory Localization File | 2.5 |
| .DIAGCFG | Troubleshooting Pack Configuration File | 2.5 |
| .IPOD | Rockbox Firmware File | 2.5 |
| .LPD | Lookout Protocol Driver File | 2.5 |
| .NETWORKCONNECT | Apple Network Connect Document | 2.5 |
| .WPH | Phoenix BIOS File | 2.5 |
| .IPTHEME | IconPackager Raw Theme File | 2.5 |
| .RS | Windows Rating System File | 2.4 |
| .QKY | Quirky Kernel | 2.4 |
| .JPN | Windows Japanese Noise-Word List File | 2.4 |
| .FID | Microsoft Catalog Indexing Service File | 2.3 |
| .TA | Sony Firmware File | 2.3 |
| .FTS | Full Text Search | 2.3 |
| .SPX | System Profiler XML Report | 2.3 |
| .INTERNETCONNECT | Apple Internet Connect Document | 2.3 |
| .MMV | Magnex Firmware File | 2.0 |
| .LEX | Spelling Dictionary File | 2.0 |
| .RCV | BIOS Recovery File | 2.0 |
| .TRASHINFO | Linux Trash Metadata File | 2.0 |
| .IUS | InfoTMIC Firmware Update File | 2.0 |
| .89U | TI-89 Titanium Operating System File | 2.0 |
| .WLU | Windows Legacy Update | 2.0 |
| .TCO2 | TI-Nspire CX II Operating System File | 2.0 |
| .KWI | Toyota Entune Update File | 2.0 |
| .FFL | Find Fast Document List | 2.0 |
| .DUB | Windows Spelling Dictionary Identifier | 2.0 |
| .EVT | Windows Event Viewer Log File | 2.0 |
| .KOR | Windows Korean Noise-Words List File | 2.0 |
| .BBFW | Apple Baseband Firmware Update | 2.0 |
| .PUSH_DEVICEID | Android Device Identification File | 2.0 |
| .FTG | Full Text Group | 2.0 |
| .EMERALD | Emerald Theme | 2.0 |
| .ROKU | Roku TV Firmware Update File | 2.0 |
| .VDEX | Validated Dalvik Executable File | 2.0 |
| .CDMP | WCS Device Model Profile | 2.0 |
| .ANN | Help Annotations | 1.8 |
| .HELP | Mac OS X Help Book | 1.6 |
| .REGLNK | Registry Editor Shortcut File | 1.5 |
| .DIFFBASE | Windows Diagnostics Tracking Diffbase File | 1.5 |
| .LM | Language Model File | 1.5 |
| .RVP | Sharp Blu-ray Player Firmware File | 1.0 |
| .ITS | Internet Document Set | 1.0 |
| .SPRX | Signed PlayStation Relocatable Executable | 1.0 |
| .SELF | Signed Executable and Linkable Format | 1.0 |
| .TBRES | Microsoft Store TokenBroker Cache File | 1.0 |