When I am trying to trade certain pokes, I get this message -
Important Message(s)

While creating this trade, the offered pokemon(s) of the trade was not found in the player(s) boxes and so the trade was not created successfully.

Was the pokemon you were trying to trade one of your main 6. If so, you might need to move it to the box to execute the trade.

No, it was in my box. And, after seeing that the trade was not made, I checked the other person's box again, he still had the stuff that we were trading, so I think its an error.

Must be, I can't think of any other reason it could be a problem except for a bug.

Its the trade caps. If it's above the trade caps you can't trade it.

yeh catchpro is right its the trade cap if its exxed the trainers trainer cap you wont be able to trade it unless its not over the players cap lvl but if the person tl is 5 or lower than 500 when your trading it wont work unless you can send that poke but cant be over tl

Its not trade caps. I am not as old player as you, but I do know that pokemon above trae cap turn grey in color and cannot be selected! Two people answered wrong lol

complanboy - no there is still some pokemon which don't get grey we know you are not new player but still experienced trainers still need to learn alot!

lol, ok thank you. i will see their levels and other person's trade cap.