Errors in vb project

[desperateboy]

During compilation following errors occurs.I have added some dll files thru add reference.

Warning: The dependency 'Billing, Version=1.0.3193.27565, Culture=neutral' in project 'BRecon' cannot be copied to the run directory because it would overwrite the reference 'Billing, Version=1.0.2271.133, Culture=neutral'.

C:\Documents and Settings\User\Desktop\BRecon\AddItem.vb(105): 'prjMas.AddItem' is defined in multiple places; using definition from 'C:\Documents and Settings\User\Desktop\BRecon\AddItem.vb'

Warning: The dependency 'prjBusLayer, Version=1.0.2271.121, Culture=neutral' in project 'BRecon' cannot be copied to the run directory because it would overwrite the reference 'prjBusLayer, Version=1.0.1.0, Culture=neutral'.