Similar to a "bad day," a Microsoft Word Day is caused by having to format something in Microsoft Word. After doing so, having a good day is pretty much impossible, so you might as well go back to bed.
Example 1:
I had to fix the page numbers in my thesis this morning and, an hour into it, I'm pretty sure today is going to be a Microsoft Word Day.

Example 2:
Student 1: Dude, why are you so grouchy today?

Student 2: I had to write a summary this morning and now I'm having a Microsoft Word Day.
by emeralddawn August 26, 2009
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