Here it is folks!
Read it and weep. (and whoever guessed it was related to some Japanese thing ought to be given a job at MS!
https://www.zdnet.com/article/microsoft-pulls-buggy-office-2010-january-updates/
Microsoft pulls buggy Office 2010 January updates
Microsoft's preparations for a new Japanese era coming later this year break Excel.
Microsoft has pulled its first updates of the year for Office 2010 after reports, mostly from Japan, that they have been breaking Excel.
The updates arrived on January 2 with changes in the Japanese calendar, most likely to reflect the changes coming with the end of Japanese Emperor Tenno Akihito's reign. He is planning to abdicate on April 30, 2019, marking the
end of the Heisei era and ushering in an as yet unnamed new calendar era.
As reported by Borncity, Microsoft pulled the January 2019 Office 2010 updates on January
5. All updates for Excel 2010 and Office 2010 included "changes to Japanese calendar".
Japanese language blogs have reported that after installing the non-security updates, users were seeing messages that 'Excel cannot be opened' and that the spreadsheet app was sometimes freezing. Excel also couldn't handle new entries in cells. Users reported
that uninstalling the updates resolved the issue.