Error message trying to network 2 computers

I recently set up a 2 computer netwrok to access the
internet through a cable modem. Internet access is working
fine. File sharing has been enabled on both machines. I'm
running XP Pro on both machines. One machine can access
the files of the other, but that machine can't access the
files of the other. When I go to my network places I can
see the folders on the machine, but When I try to open
them I get the message:

You might not have permission to use this netwrok resource.
Not enough server storage is available to process this
command.

The machine I can't access has 80 Gb drive partitioned
into a 10 Gb C: and two 30 Gb drives. 10 Gb has been left
unassigned. There is 512k of DRAM in the machine.

Can anyone help with this problem?

Bob