Based upon the %temp% variable this should work fine. However you could +R attribs or the file could be in use and it would not delete.

code:

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DEL "%TEMP%\*.tmp"
DEL "%TEMP%\*.CHK"
DEL "%TEMP%\~*.*"

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Very quick simple code. Not bullet proof and not a search and destroy method. Here is another example also.

code:

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If @InWin = 1
 RUN '%COMSPEC% RD /S /Q %TEMP%'
EndIf 
If @InWin = 2  
 Shell "%COMSPEC% DelTree /Y %TEMP%"
EndIf 

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