Question : Why couldn't these PCs connect to router, without a HUB in between?

First:
I am VERY sorry that all this is so poorly documented.  I was so tired and desperate, I was trying many things at once, and often lost track of which change had fixed what or harmed what.  I'm hoping someone can recognize the main error I made nonetheless.

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OK:

I was hired to network 4 PCs for this guy -- each with a  diff operating system:
Win98, username ABC, password XYZ
WinME, username ABC, password XYZ
WinXP Home, username DEF, password XYZ
WinXP Pro, username GHI, password XYZ.

The Win98 and WinXP Pro PCs were plugged straight into a Linksys wired cable/DSL router in the middle of the room -- which was NOT CONNECTED TO THE INTERNET!!!!

The WinME and WinXP Home PCs were plugged into a HUB -- a Netgear Dual Speed Hub, 8 port, model "DS108" -- which was THEN plugged into the SAME Linksys router (just mentioned above).

Little on the network worked.  His only internet access was provided by a THIRD device -- a (sbc yahoo) 2wire 1701HG gateway (wireless DSL router), with 4 ethernet ports.  This sat alone in the corner and only one of the 4 PCs (the XP Pro) had a wireless adapter, and was connecting to the web with that. But if you connected the same XP Pro pc to the Linksys router via a cable, you lost the ethernet connection.

He also was using some kind of "centronics to Ethernet" converter, which connected one of the printers to the Linksys router.  I did not understand how this worked, since it was not a print server, and it was not connected directly to a PC. But that's a small issue. In the end we attached all printers to a pc directly, and networked them that way.

As far as the pc networking is concerned:

I told him, why not just put the 2wire router into the middle, and connect all to that?  Instead, he initially had me try to configure a FOURTH device, a wireless Netgear router (DIFFERENT animal from the hub), to bridge the network in the middle of the room wirelessly to the 2wire router in the corner of the room. But I called Netgear, they said no, this model of router couldn't do it wirelessly, that we needed a cable to connect routers. (Obviously I need to research this bit!)

So finally, the guy agreed to let me simply run a bit of DSL phone cable into the middle of the room, and position the "2wire 1701HG gateway" wireless DSL router (4 port) there, in the middle of the work area.

At first, I just swapped the 2wire router for the Linksys router. Meaning, two of the PCs were directly connected to the new 2wire, whereas 2 PCs still had the hub between them and the 2wire.

All four PCs saw the internet, and 3 PCs networked, mostly. But the 2 PCs still on the HUB had several networking issues, so…

I said, why not get rid of the friggin hub? Connect them all right to the 2wire?  (positioning was no problem)

But as soon as I did this, and powercycled, the two PCs in question could not connect at all.  They read as disconnected and/or limited/no connectivity.

I think I checked everything.  I figured, it's got to be some kind of network config thing but I couldn't find anything… I looked all thru the network settings -- but part of the problem was, these two PCs had 2 to 3 ethernet devices each, and each had 4 different internet protocols installed (IPX/SPX, NEtbios,  Netbeui, Netbios, Aspercreme, on and on.) Therefore, somehow I missed that one PC had some setting (IP or Gateway?) set to a different network segment.  

NOTE -- either the previous router (Linksys), or the MIDDLE one I unsuccessfully tried to install,  was 192.168.0.1.  The new router (2wire) is 192.168.1.254.

So I thought, voila, that must be it, and cleared the IP shown. And now (unless I’m losing my memory), that one PC (the XP Home pc) could connect to the web -- kind of. But then it kept timing out.  It would ping www.red.com for 2 pings, then time out the 3rd ping. Shit like that. And network activity took forever, and often failed.  

So, finally, in desperation, even tho it makes no sense to me (?), I put the hub back in between those two PCs and the router.  And it fixed a ton of shit. In fact, since the Win98 PC, while it had internet, had never connected to the network by that point, I tried putting THAT on the hub too -- and it now saw the network fine!  (although by that time I had also added some usernames to xp - see below)

In fact, in the end, almost all the PCs could see all the other PCs, with one exception (see below).

Just to be clear before I go on -- before I started (when I arrived), the network was a Linksys router, with 2 PCs plugged straight into it, and 2 PCs plugged into a hub, which was then plugged into the router.  When I left, the hub was in between the new 2wire router and the WinME & WinXP Home & Win98 PCs.   Furthermore, either the first (linksys) router or the abandoned intermediate router (netgear) may have been on a different network segment than the final one.


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So I have the following main questions:

(1) Does the issue of the hub make sense? Why would 2 PCs have such a hard time connecting to the network, UNTIL I re-inserted the hub between them and a router?


(2) Which of the following things that I spent time futzing with are TOTALLY IRRELEVANT to the connectivity or network issues?

--At one point, to get the WinME and Win98 PCs to see the WinXP PCs, I added the users / passwords "ABC/xyz" to the two XP PCs, to match the users logged into the 98 and ME PCs. I think this is why the WinME and Win98 PCs could see everything once I restored the hub connection

--AT one point, I fucked with PC network settings / gateways, DNS settings, WINS, and tried messing with the NON TCP/IP -protocols mentioned above, but they didn't help

--in general, in Network Props, do I ever worry about the settings for the "adapters" with the green icons -- or only the "protocol" settings, with the "plumbing / piping" icons?

--at one point, when looking at the router config, I saw that it was blocking inbound / outbound netbeui (NetBIOS?) traffic. Does that matter? (I unblocked it, no diff)

--AT one point, the XP Pro PC couldn't see the XP Home PC, until I "allowed" the XP pro IP thru the firewall -- but that was isolated (after that I kept the firewall down, no help with other problems)

--at the end, the only remaining issue was the WinME pc could not see the WinXP Home pc.  The WinME pc also had the icon on the desktop, a "residential gateway", and it had been used as a gateway in the past. But I had made sure the IP and Gateway settings were cleared in Network Props!

--why did the screen of the XP Home pc ask for a username / pw to connect to the XP Pro pc -- but no other PC provided the opportunity (a popup window) to enter a network username / pw, when needed?



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Thanks to anyone with the kindness to struggle thru that gloop! I'm so burned!

Answer : Why couldn't these PCs connect to router, without a HUB in between?

Did you bother to check the cables which you pulled from the HUB? If you are using those cables, you should check if they are straight, and not crossed.