I play on PC, my xbox friend sends me an invitation to play (For Honor) through the game itself. I receive a notification in the xbox app, although I play through ubisoft connect, without it I can not start the game. If I open this link, it redirects me to the Microsoft store and says I can't install this game on my computer. What should I do about it?
Hey there @Bubenchik228-0 - welcome to Ubisoft Discussions!
Regarding crossplay in For Honor, so far we have introduced crossplay matchmaking to the game, but not cross-platform lobbies just yet.
This is planned however, and will be deployed as part of our Phase 2 deployment of crossplay in the game. You can read more about the plans for crossplay in the game here.
For the moment, you'll not be able to directly squad up with your friend on Xbox, however you might encounter each other randomly in a match online if you ensure to have crossplay enabled in the in-game settings!
I hope that this information helps, and please let me know if you have any other questions or concerns that you'd like me to answer. 
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