It is because the index files for the individual files have not been updated. 
A quick fix is to visit the specific list's header in the web interface and force a put command.
The button is titled "update". Click it to force a PUT. 
If that doesn't do it for you then try to search the archive with some type of bogus string (e.g., test).
This will force the index files to be created for the list archives. 
Just be sure that the list in question has been setup to have web accessible archives. 

I've just been through the same exercise moving 400+ list from a VM server to a Unix server.
I seen the error entirely to many times. 
The 2 options above have worked for me. 
I learned this trick from Paul Russell, ListServ Master. 



Mitch Rerek
Senior Information Technology Consultant
OIT Customer Support
West Virginia University
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(304) 293-4444  ext 2256



>>> [log in to unmask] 06/25/02 11:59:19 AM >>>
I'm in the process of finishing the upgrade to version 1.8e.  I've
discovered that the web-based interface to the archives no longer displays
the html version of postings.  Instead, it returns this:

>Error - Cannot Access Archive Files
>
>The archive files could not be accessed, either because the list does not
>have Web-accessible archives or because they are being updated. If you
>know that the list has Web archives, please try again in about 30 seconds,
>and report the problem if it persists for more than a few minutes. The
>file that could not be opened is
>'c:\webshare\wwwroot\Archives\upload\2588560643117459.tmp' and the error
>code was 13.

  What is causing the problem; what is the remedy?

Steve



Stephen C. Nill, J.D.
Founder & Chief Executive Officer
CharityChannel.com
(949) 589-5938
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