As far as connecting to this PC via Remote Desktop goes, please verify two things and then run a test for me.
- The Windows Service "Terminal
Services" (Control Panel,
Administrative Tools, Services) is
started (if not, right mouse click
on it and select Start, if you
cannot start, verify under its
properties that it is not disabled).
- The Computer's System Properties
"Allow user to connect remotely" (a
check box) is enabled. Located
under Control Panel>System> Remote
tab). << It looks like you already
checked this, but just to be safe I
wanted to mention again. >>
After verifying those two things, test that the Terminal Server is running and bound to a TCP port on your computer. To do this, type the following at a command prompt:
netstat -anp tcp | find /N "3389"
That should return something like this:
TCP 0.0.0.0:3389 0.0.0.0:0 LISTENING
If it doesn't, Terminal Service isn't running, or is running on a different port. You could always run something like this to see if its bound to a different port:
netstat -anpb tcp
The result would look like this:
TCP 0.0.0.0:<some number> 0.0.0.0:0 LISTENING 1900
-- unknown component(s) --
Microsoft Support Article 299357 (I'm only allowed to post one URL) describes how the listening port for RDP may have been changed from 3389 to some number.
As far as not being able to ping this computer goes...can you upload the IPCONFIG for both machines? Are there any hardware firewalls between them?
Like another member mentioned, it's possible this computer has another software firewall blocking inbound traffic, aside from the Windows Firewall. I'd check in the Security Center (which should detail if any are active).
Also, you might want to see if any TCP/IP filtering settings have been enabled for this NIC.
If nothing else, you could try resetting the TCP/IP settings...Microsoft Support Article 299357.