Networking issues

I am running a wireless network between my laptop in my room and my main PC in the study. The laptop is a Compaq Presario and the main pc is a custom made AMD Athlon XP. Both of these machines run Windows 7 Ultimate.

The problem is, on the laptop I can't seem to connect to the HOME PC computer when I double click on the the HOME PC computer in the network folder. However if I am on the PC I can access SHADOW (Laptop) and the folders that I currently have on the share without any issue.

Access the Internet from the laptop via the wireless connection is fine, as is on the main PC. So what am I missing from this problem, or what steps haven't completed to get the laptop to be able to access the shared resources from the main pc?

The message that I get on the laptop when clicking the HOME PC link is :

\\HOMEPC-PC is not accessable. You might not have permission to use this network resource. Contact the administrator of this server to find out if you have access permissions.
Logon failure: the user has not been granted the requested logon type at this computer.

The folders I want to share from the main pc are already being shared. There is no issues with that. It's the laptop that keeps coming up with that message I described every time I double click on the HOME PC computer in the network window on the laptop. I can access any shares I have from my laptop such as the Documents folder, from the HOME PC in the study. I just can't access anything via the laptop when I double click the computer icon in Network to access shares of the HOME PC computer in the study. See the problem?

Based on that error message, I somewhat missed something, the question is what did I miss or I haven't done in order for the laptop to have permissions to be able to logon to the HOME PC study computer?

Yep that's what I'm saying. I'll try and give that a shot and see what happens. :)