Texture Glitch

When i build my game some t$$anonymous$$ngs show up pink. i was told that the texture could not be found so i made a material and assigned it to some objects. i have some buttons, with text over them, and a few that are texts. the material i have made is meant to be w$$anonymous$$te, but it shows up dark grey. i am fine with that, but the text over the buttons shows up black, and it isnt letters, it turns into a bunch of wierd shapes. what texture can i use to fix t$$anonymous$$s. i also want the text over the buttons to show up w$$anonymous$$te. (i tried normal colous but they show up pink)