1.Always keep the "hide extensions for known file types" enabled in your XP box/pc.
.exe file can have the icon of an image file as shown above.
3.On keeping the "hide extensions for known file types" enabled look out for extensions like...few are listed below.
----EXE - Application
----DLL - Dynamic Link Library
----HTA - HTML Applications
----INF - Setup Information File
----OCX - ActiveX Objects
----VBS - VBScript Script File
----BAT - Batch File
----JSE - JScript Encoded Script File
there are more extensions available which are executable file extensions,to see the list (DOWNLOAD).
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