Hi!

Try this to change:

declare integer SetFileAttributes in Win32API ;
	string @ lpFileName,  integer dwFileAttributes
declare integer GetFileAttributes in Win32API ;
  string @ lpFileName

function ChangeAttrib
Lparameters tcFileName, tlReadOnly, tlHidden, tlSystem
#Define FILE_ATTRIBUTE_READONLY             0x00000001
#Define FILE_ATTRIBUTE_HIDDEN               0x00000002
#Define FILE_ATTRIBUTE_SYSTEM               0x00000004
Local lnNewAttr
lnNewAttr = iif(tlReadOnly,FILE_ATTRIBUTE_READONLY,0)+;
	iif(tlHidden,FILE_ATTRIBUTE_HIDDEN,0)+;
	iif(tlSystem,FILE_ATTRIBUTE_SYSTEM,0)
Return ( SetFileAttributes(@tcFileName, ;
	bitor(bitand(GetFileAttributes(@tcFileName),0xFFFFFFF8),lnNewAttr)) = 1 )

I see this sample in a thread here in the UT but I don´t remember the number.
Bye!

P.S.: Sorry my bad english.