The error is likely related to the Mail Windows App, though that module might perform tasks for related apps as well (the Win8 People app is another likely user). I think there were quite a few updates recently -- Why not try visiting the Windows Store (using the Windows 8 Windows Store app) and grabbing the updates for your apps. Unfortunately, it seems the updates for those apps have to be installed from the Windows Store (so far, I haven't seen their updates show up in the regular Windows Updates ... very inconvenient).
See if that helps at all.
. . . Gary
[... and howdy to J.C. Griffith! ... I'm visiting the last few days, since 8.1 is out]
