or maybe someone has an idea?
You first need to make sure that they are on the same IP subnet. Go to the C prompt and type ipconfig <enter>. For Win98, you can also run Winipcfg from Start>Run. Look at the IP address. The first three groups of numbers of the IP address should be the same for both computers if the subnet mask is 255.255.255.0 which it probably is. For example the two computers IP addresses might be something like:
192.168.1.2
192.168.1.3
If they aren't in the same range (subnet), that's the problem. If they are in the same subnet, try to ping one from the other at the C prompt. For example, on the 192.168.1.2 machine type
ping 192.168.1.3
.
Sometimes network browsing is flakey, especially with Win98. Instead try to connect directly by:
Click Start>Run
Depending upon the ip address of the other machine, type for example:
\\192.168.1.3
If it is working, the shared folders for that computer should come up in Windows Explorer.