Well without knowing the commands that you've been asked to type/paste it's a bit hard.
The messages from XDCC bots usually ask you to request "packs", so something like /msg XDCCBotNickname get MikeHammer P3 or words to that effect. Other times you may have to wait for the bot to DCC chat you, and then use the commands in the DCC chat window to request a file.
If it's an Fserve, it's likely that the person sending the messages isn't a bot, but rather a real person. In that case, try messaging them. You can check their idle time with /whois nickname nickname. The longer the idle time, the more likely it is that their away from the computer.
It could be a problem or bug with the Fserve script that is making it not send, in which case that isn't yours or the senders fault, but the author of the script their using.
Either way, there's not much we can do this side, it seems to be all down to the sender or their script rather than a problem with settings you have. To echo what ParaBrat posted, make sure you read /help /fserve it's a good help file.
G'luck, and I hope when you do get it, it's a good read =)