All XP home LAN - file-sharing stubborn bewteen just 2 systems

[MilesG]

I'm in the UK and have a Main computer (XP) that connects by ethernet to the
BT Home Hub H (version 6.2.6.E) and a wireless LAN consisting of 3 other
desktops and a laptop, all XP. I've had no big problems over the months I've
set up file- and printer-sharing other than the typical Zone Alarm matters of
ensuring the IP range is covered.
I've suddenly lost file-sharing ("not accessible... might not have
permission... network path not found") between the laptop and the Main
desktop. Neither wishes to share with the other, although they see each
other, and ping each other ok, as do all the others. All the others are ok
and can file-share as normal amongst themselves and the Main one. The laptop
shares OK with the others. It's just the laptop and Main that are having a
spat.
I've tried in vain setting up a whole new network name. I've tried in vain
opening a new folder in each to share in the hope it might trigger some
action. And I tried in vain deactivating Zone Alarm on both at the same time.
I feel sure it's an XP file-sharing issue, but can think of nothing else to
try.
File-sharing is not something I do on a regular basis between the laptop and
the Main system, but I suspect that this may be a post SP3 symptom - SP3 is
on all systems now.
I've enabled the Guest account on both systems.
Any ideas please?

Miles

 

[Guest]

I note you are using Zone Alarm , have you set the LAN in the trusted zone,
this might just be the problem

deejaydee

 

[MilesG]

Yes I did, thank you deejaydee. When I've had file-sharing issues before I've
usually found that it's a firewall matter. I've got the range 192.168.64-100
in the Trusted Zone on all systems on the LAN.
And, just to make sure it wasn't a ZA matter I disabled ZA on both
recalcitrant systems to no effect.
Miles