I can confirm that I am seeing the same behaviour in Excel 2002 with your file.
I saved a copy locally and the link updated fine on opening the master file.

So it seems to be a problem specific to the use of the web to get the value.
I have so far failed to find any references to this behaviour in the knowledge base etc.
I will investigate further when I have more time

Bill Manville
MVP - Microsoft Excel, Oxford, England
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