The fact that mIRC has dcc capabilities does not mean that you can freely distribute and/or "download stuff" from xdcc bots... and, as far as I know, there isn't such thing as an Options > XDCC menu. And, of course, there's no reason here to use (or intend to use) foul language...
As for your question, normally (I would say, 90% of the times), issues with resuming dcc transfers are due to problems on the sender's end, not yours, so ask your "friend" to re-send the file, or use the search feature of this forum... I'm sure (because I've read them before) that more than a few results may come up.
Regards.