The ~ (tilde) should not be attached to your nickname, it should be on your IdentD (nick!~identd
@hostname). This means that IdentD is not installed properly. You need to use port 113 and type /identd on
Further suggestions for enabling IdentD can be found in this thread
DCC sends being erratic is a little strange, if one person can connect to you, then they all should be able to - it could be conflicting port usage or even to do with the mIRC version. Try looking at the Can't DCC Send thread
Out of interest, why are you sending 100-150 files everyday? Why are you downloading?
- this post
may interest you.