nikkey

First i'm going to say somthing you probably don't want to hear. "I'm not a MAC Guy". Thats why im posting here.

I could use help. Our company only has 9 MAC computers, which are used for our ART Department employees only. We have a mixture of OS's for them. 3 of them run on OSX 10.4 Tiger, the rest run on OSX 10.2.8. We haven't had any networking issues before. Only starting about 3 weeks ago, the mac users seem to lose partial network connection. They notice it when they can't connect to eachothers stations. Its also random. I.E...station 1 can connect to everyone except station 5, station 5 can connect to everyone except station 2...and on and on. When this starts to happen, if they pull up their network chooser to see if they can see everyone in the workgroup, they will notice that they can't. And even the users they DO see, they may not be able to connect to them. They will just get Time Out Errors. Oddly as well, they found if they try to connect directly by IP Address, they can do so. But not through the chooser all the time anymore.
Once again this probably started recently, withen the last few weeks. As far as i know, no new software or hardware changes have been made. I have verified the network settings on each machine, and the network router is new.At first they started to get disconnected from a Shared External MAC Drive thats connected to one of the MAC Computers (The system that has the external drive on it, isn't used by anyone, it just hosts the hard drive). We have PC Users in our web department who also access the External Drive on a regular basis, and they will not have any trouble accessing this drive or get disconnected from it, even when the MAC users at that very second are having trouble. So the problem seems to be isolated the MACS only, and i'm not sure why. Once again i'm not a MAC person so i don't know what i could be overlooking at this point.
I hope i have provided enough information so far. Thank you for your time.