| .xaml |
XAML File |
| .xmb |
X-Wing Mission Briefing File |
| .xsn |
InfoPath Form Template File |
| .xs |
Age of Empires 3 Map AI Generator |
| .xpr |
Pro/ENGINEER Part Instance Accelerator File |
| .xlw |
Excel Workbook |
| .xtp |
xTime Project Document |
| .xnb |
XNA Game Studio Binary Package |
| .x |
DirectX Model File |
| .xui |
Xbox 360 dashboard skin files, XML User Interface files |
| .xur |
Xbox 360 Binary User Interface File |
| .xej |
Expression Encoder Job File |
| .xel |
Expression Encoder Live Encoding File |
| .xesc |
Expression Encoder Screen Capture File |
| .xpp |
X++ Source Code File |
| .xsf |
InfoPath Form Definition File |
| .xamlx |
Visual Studio Workflow Service File |
| .xsc |
Visual Studio Dataset Internal Info File |
| .xvd |
Xbox Virtual Disk |
| .xl |
Excel Spreadsheet |
| .xsb |
XACT Sound Bank |
| .xwb |
XACT Wave Bank |
| .xgs |
XACT Global Settings File |
| .xrm-ms |
Microsoft Security Certificate |