I'm not sure what you mean by "the files will not be shared automatically". Do you mean that you don't see any uploads (other people downloading your files)?
During your LW session, go to LW's library & check the uploads column...figure on the right shows attempted uploads & figure on the left shows successful uploads.
You can also go tools > options > bug reports > view example. Scroll down to 'recieved incoming this session' - if it's false then you're not recieving incoming connections from other computers (probably a firewall issue). Do you see the firewall icon (brick wall in front of the blue globe)?

If you give us your details, we might be able to help a bit more
System details - help us to help you -> Provide these details when you post!!!