MYKEY's Ethereum address is a contract account. However, only a few exchanges accept deposit from a contract account. Hereby is the list of exchanges verified by MYKEY Lab. MYKEY users could choose any of them in prior to deposit and trade. (Withdrawal from the exchange to the MYKEY account are not affected regardless of the list. )
The user could send a request to the exchange if he accidentally deposit from MYKEY to those exchanges which don't support the contract. The exchanges will process manually in most cases otherwise the user may ask MYKEY for further assistance.
If the exchange supporting contract deposit is not on the list, you can submit a PR in github.