You should not be using XDCCs in conjunction with mIRC - it is:

- illegal, and can end you up with fines. Big ones.
- A big way to get viruses.
- Against the very nature and meaning of IRC/mIRC.

However, type /remote off and then try an irc:// link. Try rebooting, then using the link. Also make sure you're using Internet Explorer with this service, it will not work with other browsers.

See if a Search runs anything up - expand to 'All Forums' and 'All Posts' in order to get the best results.