I know this has been touched on, however the solutions that work for others do not seem to satisfy my stupid computer.
Computer A can see and access Computer B and vice-versa. Computer A and Computer B can see Computer C but cannot access. Computer C cannot see or access Computers A and B. All are part of the same Subnet all are directed at the correct gateway all have Windows Firewall diabled and all are XP Pro SP3 machines. A and B are hardwired C is wireless.