Explorer tries to write DLLs when searching Windows

[hmb_puzzled]

When using 'My Computer' to Search for any file name in the C:\WINDOWS
directory, Explorer (not IE) tries to write a number of files. (Details at
end)

It does this _only_ when searching C:\WINDOWS. I tried searching other
directories and it keeps quiet.

So a number of questions arise:

* Is this expected behaviour? I certainly would not expect search -
essentially a read only application - to be writing files.

* Is this indicative of some virus? Antivir does not think so, but a
sophisticated virus can defeat any virus checker.

* Is there a cure?

I am running XP Pro. v 5.1, Build 2600 xpsp_sp3_gdr.090804-1435 : Service
pack 3.

The files being written by explorer.exe are:

C:\WINDOWS\SYSTEM32\legitcheckcontrol.dll
C:\WINDOWS\OPUC.DLL
C:\WINDOWS\SYSTEM32\MUWEB.DLL
C:\PROGRAM FILES\JAVA\J2RE1.4.1_01\BIN\NPJPI141_01.DLL
C:\WINDOWS\DOWNLOADED PROGRAM FILES\INTRALAUNCH.OCX
C:\PROGRAM FILES\JAVA\J2RE1.4.1_01\BIN\NPJPI141_01.DLL
C:\PROGRAM FILES\JAVA\J2RE1.4.2\BIN\NPJPI142.DLL
C:\WINDOWS\SYSTEM32\MACROMED\FLASH\FLASH10C.OCX

There may be other, non-executable, files being written too, but my software
does not intercept or report those.

Thanks