error if texmf.fndb and mpm.fndb are not writable, even if no write is occuring

I need to be able install MiKTeX on a customer's Windows XP box in their 
Program Files folder. They have a requirement that no files in this 
folder can be modified by users and, more generally, that no files in 
Program Files can be writeable.

To prototype this, on my own Windows XP box, I ran MikTeX (pdflatex) on 
a tex file that causes all the packages they need to be downloaded. I 
verified that when I run pdflatex a second time, the files texmf.fndb 
and mpm.fndb do not change. I then turned off the write permission on 
these files and ran pdflatex again. I then got the error

pdflatex: Windows API error 5: Access is denied

If I ran

pdflatex -disable-installer

I got the same error.

It seems that in this situation it should not be necessary for 
texmf.fndb or mpm.fndb to be writeable, especially because I can verify 
that the contents and time stamps of these files are not changing.

Am I doing something wrong or is this a bug?


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