Problem with switch/router

StephenM

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I have a fibre optic broadband modem connected to a Technicolor router.

The router has three additional network cables connected:
1. To my computer
2. To Sue's computer
3. To a Netgear Gigabit switch

The Switch has additional cables to:
1. Server 1
2. Server 2
3. Laser printer
4. Photo printer

Everything works fine. I can access any device from this computer, and the internet.

Now the problem.

If I connect my computer directly to the switch, it loses all connectivity, and Windows (it's running Win 7 64 bit) says that there isn't even a network cable attached.

It does not appear to be a problem with the cable, since using the same cable to connect computer to router works fine. As is the case with two other cables I've tried.

And the same happens with Sue's computer (also Win 7).

The setup I'm trying to duplicate worked before fibre optic, and before I changed switch (the old was identical model but overheating).

Any ideas?

PS I've tried rebooting everything with no effect.
 
Afraid so...
 
Some kind of duplex mismatch, or is are the speds of the ports set differently?
Oh, and some routers wll accept a crossover cable between the PC and router, but I doubt many switches do, so could it be you're using crossover cables by mistake?
 
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As far as I know, speed selection is automatic.

The old setup (which worked perfectly) didn't have a fibre optic modem, so it was

Router: cable to phone point; cable to swtich.

Switch: cable from router, plus cables to 4 computers and one printer.

Fibre optic change occurred at same time as switch failed - replaced by identical model. Plugging the same cables into the new switch, and at the other end plugging into the new router, meant that the two servers (WinHomeServer) worked perfectly - visible on network, have access to internet for service packs; printer accessible also. But the two Win7 computers simply said that there was no network cable conected. Putting cables from router to Win7 computers, and all is fine. Not the same cables, since the originals are long and go round three sides of the room (router on one wall, with desktop PCs; switch, servers and printer against opposite wall).

However, I have tried the same cable which works when connected between PC and router, and is "not present" when plugged into switch instead.

I'd believe it was a Win7 issue (it was a pig to set up netwoeking, and it still won't talk to Win XP) except the OS hasn't changed - just a newer version of the same switch and a new router.

I've tried all available points on the switch (there are 16!) and ones that work stop working when it's the Win 7 PCs. I've tried all the cables I have, even to the extent of moving the switch nearer to try short ones. Everything has been rebooted, in every combination of sequences I can think of. But still 2 different printers and two servers work fine, and two Win 7 computers don't.

The only thing I haven't tried is using a static IP address - but I can't see the point if the network cable isn't being recognised at the PC end.

My best guess has to be to connect it in some way with the Technicolor router (TG582n) supplied by my ISP. But I can't see why the PC reacts as it does. It does say that the cable isn't connected when I unplug it from the router, so the prima facie explanation is a cable fault or swtich fault; but given my cable and port swaps I can't square it with the situation.

Thanks for the suggestions so far - it must be something so blindingly obvious that I've missed it.
 
I'm assuming that your switch is a GS116? In which case it should have auto-uplink capabilities and thus potentially ruling out the crossover cable theory. If this is the case, go into the properties of the network connection, then go to the adapter properties and change the speed/duplex to a lower level, usually you will have the option of 100Mbps Full, 100Mbps Half, 10Mbps Full and 10Mbps Half. Start at the top and work your way down until hopefully it says there is a cable connected. Negotiation failure can occur on faulty/miswired cables. Silly question, but did you wire the cables yourself or are they premade?
 
1. Correct as to the switch.
2. Cables pre made.

Most importantly - changing from auto to 100Mbps Half Duplex (the first one I tried) worked. I can experiment to see what I can get away with; but I'm still mystified why swapping one GS116 for another (and keeping the same cables and PC) had this effect.

Many, many thanks. It's been a problem for quite a while, but it's only become usgent to fix when I needed to have another port available.

:ty:
 
I'm probably stuck with it, as I've had it while before the problem became a pressing one to solve mainly because I need to connect another printer, and I can manage a cable from my darkroom door and along the corridor to the router which is just inside this room (about 16 feet), but not across the room as well.
 
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