Downloaded the latest Windows upate, and now my Excel file is corrupted.

Yesterday, I downloaded the latest Windows update, and today I tried to save changes to an Excel file that I've been using successfully for several years.  Unfortunately, just by entering and trying to save new data into the file, it automatically crashed, and when Excel tried to recover it, it didn't help at all.  Basically, it didn't matter whether I tried to save the recovered file or the original one-- every version that I tried to save would crash without saving the new data.  The problem appears to be specific to one very large worksheet in this one Excel file.  When I enter and save new data in other worksheets in this file, everything is just fine.  I have also tried opening and modifying other Excel files on my computer, and changes to them save just fine, so I think the problem is just this one file I have, not all my Excel files.

I tried to fix things by getting a download called Stellar Phoenix that was supposed to fix corrupted Excel files, but that didn't help either.  I now have a request to Stellar Phoenix to look into the problem, but while I wait to hear back from them, is there something else I can do?