| afz | Ancestry.com Family Tree Database Backup |
| afzplug | Corel AfterShot Pro Plug-in |
| aga | ArcGIS ArcGlobe Data |
| agb | Game Boy Advance ROM Image |
| agd | AgileGraph Data File |
| agdb | ANSYS DesignModeler Data |
| ageo | Dream Aquarium Fish Model |
| agf | Zemax ASCII Glass Catalog |
| aggr | Adobe Captivate Aggregate Data |
| agl | Agile XML Archive |
| aglib | Adobe Photoshop Lightroom Library |
| agprefs | Adobe Photoshop Lightroom Preferences Data |
| ags | AGS Data File |
| agsc | XWE Data |
| agt | PeerAgent Typed Executable E-mail Data |
| ah | SEED AH Seismogram Data |
| ahb | AIM High Briefcase Report Data |
| ahead | SCAMP FITS Image Header |
| ahk | AutoHotkey Script |
| ahl | eMule Metadata |
| ahm | Acoustic Head Map File |
| ahn | Our Family Tree Data |
| ahp | Autodesk AutoCAD Help Data |
| ahstore | Microsoft SQL Server Property Hash Store |
| ahu | Adobe Photoshop Hue/Saturation Layer |
| ahv | Interfile 3.3 AHV File |
| aia | ANDI/netCDF Chromatography Data |
| aide | AIDE Data |
| aidf | AI BiddingCockpit 8 Specification Sheets |
| aif | SmartWare Executable Program |
| aii | Telerik Test Studio Test Definitions File |
| aiilist | Telerik Test Studio Test List |
| aij | Oracle Database After-Image Journal |
| ail | AutoImager List |
| aim | AIMMS ASCII Model File |