Thank you for your input, Jason. We often seem to be "lucky" this way. I am going to look into various possibilities. It was just very coincidental - applied the update and advanced search stopped working right.
I did some more testing here and I see that we do get results in advanced search - but no results after the update. Any results are messages received before the update. So if "Smith, Joe" sent me two messages, one on Friday the 28th before the update, and one on Saturday March 1 after the update, if I search on FROM:SMITH advanced search only displays the one from Friday. A regular search gives both.
If anyone has any thoughts on how I might fix this, I am open to suggestions. Thanks, Dulce (pcpix)