A customer called in a kind of panic today when everybody started getting this popup when launching Outlook:
Which says (so Bing/Google will pick it up):
This is your first login attempt or your password has expired.
You must change your password before proceeding.
These happened for multiple versions of Outlook on several different operating systems, and these did not correspond with real Windows password expirations.
This turned out to be a toolbar from a VoIP system (which has both Outlook and IE toolbars). This is a branded product, and I've seen references to the same toolbar from Alteva, DSCI, and Broadsoft: I can't tell who is the real vendor.
Vendor, if you're reading this, please consider putting some kind of branding on the dialog box so the purpose is obvious - a bit of searching on the internet shows that more than one person has been surprised by this.
Friedl's rule of tech support: the best support is that which is not needed.