I never received any responses to my issue, but I finally resolved it myself. I believe it was Dick Watson who suggested to another poster that he set up a test account and try to update. I used Microsoft's sample file, created the mutual fund accounts that
I previously could not update, and was able to update those mutual funds. I then went back to my money file and selected "update price", selected "pick quotes to download" and UNCHECKED the boxes for the mutual funds that were not updating.
I then updated the prices again. Then I RECHECKED the boxes for the mutual funds that were previously not updating and this time they updated correctly.
When I first encountered the update problem I UNCHECKED and RECHECKED the quote boxes, so I'm not sure how the problem got resolved this time. I do notice now that although the current price for Friday 8/6/2010 has been updated in all my mutual funds, there
is still a history gap for the mutual funds that had not been updating since 6/4/2010. That is, the online updating for those mutual funds stopped on 6/4/2010 and resumed on 8/6/2010 and the dates in between have not updated, as they should.
Oh well. I chalk it up to a glitch at Microsoft's end that finally got resolved.