MEW and Metamask are ERC20 wallets that can be used to send and receive MDX. However, to use it for MDX you may need to add MDX as a custom token.
Follow the instructions shown for either MyEtherWallet or Metamask, depending on which wallet you are using. The contract information for MDX is given at the bottom of this article.
NB: Please ensure you choose the correct version of the MDX token for what you have in your wallet. V1 is the old version of the MDX token from the original token sale. V3 is the current MDX token used on the exchange.
To check what version of token you have, please follow the instructions given here.
MyEtherWallet custom token - https://kb.myetherwallet.com/en/tokens/how-to-add-custom-token/
Metamask custom token - https://metamask.zendesk.com/hc/en-us/articles/360015489031-How-to-View-See-Your-Tokens-and-Custom-Tokens-in-Metamask
Current V3 MDX
Contract - 0x947AEb02304391f8fbE5B25D7D98D649b57b1788
Token ticker symbol - MDX
Decimal - 18
OLD V1 MDX
Contract - 0x9d03393d297E42C135625D450C814892505F1a84
Token ticker symbol - MDX
Decimal - 18