Starting with a character: : X

File extension	Full name
X File Extension	DirectX Model File
X32 File Extension	Adobe Xtra File
X3D File Extension	Xara3D Project
X3F File Extension	SIGMA X3F Camera RAW File
X4K File Extension	XML4King Configuration File
X64 File Extension	Commodore 64 Disk Image
XA File Extension	The Sims Audio File
XADD File Extension	Expression Web Add-in
XAF File Extension	3ds Max XML Animation File
XAIML File Extension	XAIML Chatterbot Database File
XAML File Extension	Windows Markup File
XAMLX File Extension	XAMLX document file
XAN File Extension	Worms Map File
XAP File Extension	Silverlight Application Package
XAPPL File Extension	Spoon XML Application Configuration File
XAR File Extension	Xara Xtreme Drawing
XAS File Extension	Pro/ENGINEER Assembly Instance Accelerator File
XBA File Extension	OpenOffice.org Basic Module File
XBAP File Extension	Microsoft Silverlight application package
XBC File Extension	SMART Notebook File
XBDOC File Extension	Xiosis Scribe Document
XBE File Extension	Xbox Executable File
XBEL File Extension	XBEL Bookmarks File
XBK File Extension	XenServer Backup File
XBL File Extension	Extensible Binding Language File
XBM File Extension	X11 Bitmap Graphic
XBPLATE File Extension	Xiosis Scribe Template
XBSAV File Extension	Mass Effect 2 Xbox Saved Game
XBT File Extension	SMART Notebook Template File
XCAPPDATA File Extension	Xcode App Data File
XCARCHIVE File Extension	Xcode Archive
XCDATAMODEL File Extension	Xcode Core Data Model File
XCDATAMODELD File Extension	Xcode Core Data Model File
XCF File Extension	GIMP Image File
XCODE File Extension	Xcode Project
XCODEPROJ File Extension	Xcode Project
XCSL File Extension	CineStyle Color Correction File
XCSNAPSHOTS File Extension	Xcode Snapshot
XCU File Extension	OpenOffice.org Configuration File
XCWORKSPACE File Extension	Xcode Workspace File
XDB File Extension	Symantec Virus Database File
XDI File Extension	WinArchiver Extended Disc Image File
XDL File Extension	XML Schema File
XDP File Extension	XML Data Package
XDR File Extension	XML-Data Reduced File
XDS File Extension	LCDStudio design file
XDW File Extension	Fuji Xerox DocuWorks File
XEF File Extension	WinAce Encrypted File
XEJ File Extension	Expression Encoder Job File
XEL File Extension	Expression Encoder Live Encoding File
XEM File Extension	PowerDesigner Model definition File
XEN File Extension	Guitar Hero III Data File
XENSEARCH File Extension	XenCenter Saved Search File
XEP File Extension	eManager File Packaging Information
XER File Extension	Primavera P6 Project File
XES File Extension	eManager Skins Definition
XESC File Extension	Expression Encoder Screen Capture File
XET File Extension	eManager Process Definition
XEV File Extension	eManager Auto-Update File
XEX File Extension	Xbox 360 Executable File
XEZ File Extension	eManager Template Package
XFD File Extension	XFD File
XFDF File Extension	Adobe Acrobat XFDF File
XFDL File Extension	XFDL File
XFL File Extension	Flash Movie Archive
XFN File Extension	Ventura Printer Font
XFO File Extension	XSL-FO Formatted Form
XFR File Extension	Ventura Publisher bitmap editor font file
XFS File Extension	Gunbound file
XFT File Extension	Adobe Form Designer 5.0 File
XGML File Extension	Graph Modeling Language XML File
XGMML File Extension	XGMML Graph File
XGP File Extension	Xfire Game Patcher File
XGS File Extension	XACT Global Settings File
XHT File Extension	XHTML File
XHTM File Extension	Extensible Hypertext Markup Language Document
XHTML File Extension	Extensible Hypertext Markup Language File
XI File Extension	Fasttracker 2 Extended Instrument File
XIB File Extension	Interface Builder File
XIF File Extension	ScanSoft Pagis File
XISE File Extension	Xilinx ISE Project File
XL File Extension	Excel Spreadsheet
XLA File Extension	Excel Add-In File
XLAM File Extension	Excel Open XML Macro-Enabled Add-In
XLB File Extension	Excel Toolbars File
XLC File Extension	Excel Chart
XLD File Extension	Excel Database File
XLF File Extension	XLIFF Document
XLGC File Extension	ExpressK Database File
XLIFF File Extension	XLIFF Localization File
XLK File Extension	Excel Backup File
XLL File Extension	Excel Add-In File
XLM File Extension	Excel Macro
XLMV File Extension	Thunder Mall video file
XLNK File Extension	XML Shortcut File
XLR File Extension	Works Spreadsheet
XLS File Extension	Excel Spreadsheet
XLSB File Extension	Excel Binary Spreadsheet
XLSHTML File Extension	Microsoft Excel HTML Spreadsheet
XLSM File Extension	Excel Open XML Macro-Enabled Spreadsheet
XLSMHTML File Extension	Microsoft Excel MIME HTML Spreadsheet
XLSX File Extension	Microsoft Excel Open XML Spreadsheet
XLT File Extension	Excel Template
XLTHTML File Extension	Microsoft Excel HTML Spreadsheet Template
XLTM File Extension	Excel Open XML Macro-Enabled Spreadsheet Template
XLTX File Extension	Excel Open XML Spreadsheet Template
XLV File Extension	Excel Visual Basic Module
XLW File Extension	Excel Workspace File
XM File Extension	Fasttracker 2 Extended Module
XMAP File Extension	XMind 2007/2008 Workbook
XMB File Extension	Age of Empires Game Data File
XMCD File Extension	Mathcad Worksheet File
XMCDZ File Extension	Mathcad Compressed Worksheet File
XMCT File Extension	Mathcad XML Worksheet Template
XMD File Extension	Extended Media Disc Image
XMF File Extension	Cal3D XML Mesh File
XMI File Extension	XML Metadata Interchange File
XMIND File Extension	XMind Workbook File
XML File Extension	XML File
XMLPER File Extension	LeCroy Binary Waveform File
XMM File Extension	3ds Max XML Animation Map File
XMMAP File Extension	MindManager XML Map File
XMP File Extension	Extensible Metadata Platform File
XMPZ File Extension	Miradi XML Project File
XMV File Extension	Xbox Media Video File
XMZ File Extension	FastTracker 2 Extended Module
XNB File Extension	XNA Game Studio Binary Package
XNK File Extension	Exchange Shortcut
XNT File Extension	QuarkXPress Extension File
XOF File Extension	Reality Lab 3D Image File
XOL File Extension	Swiss Map Overlay
XOM File Extension	Worms 3D Object File
XOML File Extension	Windows Workflow File
XP File Extension	WindowBlinds temporary file
XP2 File Extension	XPilot NG
XP3 File Extension	KiriKiri Package File
XP4 File Extension	KiriKiri Package
XPADDERCONTROLLER File Extension	Xpadder Controller Profile
XPD File Extension	XML Pipeline Document
XPDL File Extension	XPDL Module
XPG File Extension	Autoplay Media Studio Exported Page
XPI File Extension	Mozilla Installer Package
XPJ File Extension	RoboHelp HTML Project File
XPK File Extension	PSpice library file
XPL File Extension	X-Plane plug-in file
XPM File Extension	X11 Pixmap Graphic
XPP File Extension	X++ Source Code File
XPR File Extension	Pro/ENGINEER Part Instance Accelerator File
XPS File Extension	XML Paper Specification File
XPT File Extension	Mozilla Firefox Component
XQ File Extension	XQuery File
XQL File Extension	XML Query Language File
XQM File Extension	XQuery Module
XQT File Extension	SuperCalc Macro File
XQUERY File Extension	XQuery Source Code File
XQY File Extension	XQuery Source File
XRF File Extension	WordSearch cross reference file
XRFF File Extension	Extensible Attribute-Relation File Format
XRM-MS File Extension	Microsoft Security Certificate
XRNS File Extension	Renoise Song File
XRP File Extension	RationalPlan Project File
XRY File Extension	XRY Data File
XS File Extension	Age of Empires 3 Map AI Generator
XSB File Extension	XACT Sound Bank
XSC File Extension	Visual Studio Dataset Internal Info File
XSD File Extension	XML Schema Definition
XSF File Extension	InfoPath Form Definition File
XSI File Extension	Softimage XSI 3D Image
XSIADDON File Extension	Softimage Add-on File
XSL File Extension	Microsoft SharePoint WorkSpace Groove database file
XSLIC File Extension	XenServer License File
XSLT File Extension	XSL Transformation File
XSN File Extension	InfoPath Form Template File
XSP File Extension	XBMC Smart Playlist File
XSPF File Extension	XSPF Playlist File
XSS File Extension	XML Style Sheet
XST File Extension	Microsoft Outlook personal folders file
XSVF File Extension	Xilinx Serial Vector Format File
XSX File Extension	Visual Studio XML Schema Layout File
XT File Extension	Xdebug Trace File
XTG File Extension	QuarkXpress tags file
XTL File Extension	Vietcong Data File
XTM File Extension	CmapTools Exported Topic Map
XTP File Extension	AutoCAD Exported Tool Palettes File
XTREME File Extension	Winstep Xtreme Theme Pack
XUI File Extension	Xbox 360 User Interface File
XUL File Extension	XML User Interface Language File
XUR File Extension	Xbox 360 Binary User Interface File
XV0 File Extension	Lattice XVL Structure File
XV3 File Extension	Lattice XVL Geometry File
XVA File Extension	XenServer Virtual Appliance File
XVCT File Extension	VISE XML Project File
XVID File Extension	Xvid-Encoded Video File
XVM File Extension	VMware Console Configuration File
XVMCONF File Extension	World of Tanks XVM Configuration File
XWB File Extension	XACT Wave Bank
XWD File Extension	X Windows Dump Image
XWF File Extension	OmniPage Workflow File
XWK File Extension	Crosstalk Communicator Keyboard Mapping File
XWP File Extension	XMLwriter Project
XWS File Extension	Xara Web Designer Graphic
XX File Extension	XXEncoded File
XXD File Extension	Brixx Planner Calendar
XXE File Extension	XXEncoded File
XXX File Extension	Compucon Singer Embroidery File
XY File Extension	XYWrite Document
XY3 File Extension	XYWrite III Document
XYP File Extension	XYWrite Plus Document
XYS File Extension	XYplorer Script File
XYW File Extension	XYWrite for Windows Document
XYZ File Extension	Molecule Specification File
XYZV File Extension	Celestia Sampled Trajectory File
XZ File Extension	XZ Compressed Archive
XZFX File Extension	ZipLogix ZipForm File
X_B File Extension	Parasolid Model Part File
X_T File Extension	Parasolid Model Part File