Fill

[hedyeh99]

For some reason, fill doesn't work whatsoever in Illustrator. At this point, I think it's a bug. 

The rectangle is supposed to be filled with that gray color, the color just doesn't work. 

[Monika Gause]

Please show layers panel and appearance panel.

[Jacob Bugge · Accepted solution]

hedyeh,

If you select the (whole) Layer, the Appearance palette may give the answer, such as 0 opacity or no fill (presuming the rectangle is not part of a Group or something, in which case a crucial appearance might be applied there).