Anyone using Microsoft Exchange Server might be in for a surprise, in the form of empty inboxes or mails not being delivered.
They use a long to hold the date (E.g. 20220101000001), which is now too small to contain the numeric long form date. This affects the spam and virus checking system.
We are using a third party system, so I am waiting to see if and how we are affected, when I get to work tomorrow!
Happy New Year, from Microsoft!