There's this robin that's been flying into my window for 2 weeks every day?

He may be seeing his reflection in the glass. Try putting something with contrasting color up in the window, but wont offend people when they look (cause you know people are nosey) Try construction paper or maybe even a picture of an animal.

It most likely see's it's reflection in the window and it is attacking the invader. Try putting something on the outside or inside of the window to stop the reflection. It's probably a female with young in a nearby nest.

I agree w/ the male part! Birds used to hit my kitchen window all the time. Assuming they thought it was open space, I hung a suncatcher on the window & they stopped flying into it.

NO its because of the glass. Its common among birds. I suggest cutting a sillouette out of a predator bird (like hawk) and tape it to window. Or, turn the lights off and / or close blinds / drapes

He's probably fighting his reflection. Put something on the outside of the window in the spot he attacks, so he won't see himself there anymore.

The glass causes him to see his reflection, which he thinks is either another bird that he needs to fight with, or mate with.

it likes the atmosphere and it is probably just temperature right.put a few crumbs in a bowel etc you will find it will become very quiet,i had one for 2 years.

cookim up a nice earthworm & a chaser,,,,,,,maybe some nice mullet crunchy wunchies as a dessert

if you have brightly coloured curtains then it probably likes them thats what happened to me until we took them down