The only version of the MDX token that can be used on the exchange is the current V3 MDX token on contract number 0x947AEb02304391f8fbE5B25D7D98D649b57b1788
To find out what version of the MDX token you have, please follow the instructions below.
Visit https://etherscan.io/
Enter your wallet address into the search bar and press search.
In the 'Overview' section, click the little framed box (highlighted in the picture below)
If you have any MDX tokens, they will be shown here. Click the MDX Token entry in your list of tokens.
The token information is shown in the panel on the right of the screen. See the notes below to identify which token you have.
Current V3 MDX
Contract - 0x947AEb02304391f8fbE5B25D7D98D649b57b1788
Token ticker symbol - MDX
Decimal - 18
Deprecated V1 MDX
Contract - 0x9d03393d297E42C135625D450C814892505F1a84
Token ticker symbol - MDX
Decimal - 18
Deprecated V2 MDX
Contract - 0xAbE8585F80aDb22e3660320830b9ec708258A7e2
Token ticker symbol - MDX
Decimal - 18
V1 & V2 tokens will not send over the ETH network as the contracts are permanently locked.