Losing shared connections after random time interval

Hello guys,

I have setup a small network with 3 computers : 2 * WIN98, 1 * Win2K
An old PI 166MMX with Win98SE on it is used as server :
proxy , www, ftp & DHCP server (Lan609) for internet connection over ADSL
SyGate Firewall
print server for other pc's

Setting up the network went quite easy. But now I'm having some problems
with sharing printers and files on my server. After a random time interval,
the server stop sharing its drives and printers.
Allthough sharing has stopped, I still have access to the internet, so the
proxy is still running.
Pinging to the server also works when sharing has stopped.

I took a look at the 'System Information' from Win98 and it mentions a
problem (0xA) with VSERVER.VXD in the '\0003' part of the registry key. When
I reboot the server, all problems are gone and sharing is OK for another
couple of hours (or minutes in the worst case), until it drops after a
random amount of time.
I have installed DrWatson to let me say when and where a problem has
occured, but DrWatson doesn't mention anything at all.

I have already searched newsgroup and knowledge base at Microsoft, but
nothing has come up yet. Anyone has got an idea ?

By the way, the server I'm using has the following hardware :
p1 166MMX, 96 MB RAM
DLINK DFE530TX network card
HP4L & HP990C shared printers
Alcatel USB Speedtouch modem
The server is connected to my LAN with an EDIMAX ES-3108P switch.

My OS is : Win98 SE 4.10.2222 A
VSERVER.VXD also has this version.

Please remove NOSPAM from my email address in order to reply ...

Frederic