why the error ip configuration not valid pops up?

[technologicalpixel]

basically all my pc connected with ethernet to the modem, sometime work and sometime don't, when they don't i get the error "ip configuration not valid"

This is happening from when i changed my modem/internet connection , probably is configured bad but i have no idea of how to check it

This problem pops up only on pc connected with ethernet, all wifi device are connected and have no problem

also if i change the spot of the ethernet cable multiple times then it work again, or if i do right click on the internet icon in the bottom right of windows and then "troubleshooting"

Does anyone know why is happening and how i can fix it? thanks!

[Nuh_]

14 hours ago, technologicalpixel said:

also if i change the spot of the ethernet cable multiple times then it work again, or if i do right click on the internet icon in the bottom right of windows and then "troubleshooting"

change the spot of the ethernet cable on the modem or pc?

[technologicalpixel]

modem

[Nuh_]

I can't see where things can go wrong, nonetheless here are a couple things to try

 

on your pc open Control Panel\Network and Internet\Network Connections and click change adapter settings; click on your ethernet interface and select properties, internet protocol version 4, make sure to have get IP address automatically.

 

on your modem, look at the Modem's LAN IP and subnet mask, then make sure that the modem's DHCP settings have the same subnet mask and have a valid pool of IPs.

[technologicalpixel]

yes the subnet mask is the same,

yes on the pc the ip address are taken automatically

 

but how do i check if the modem has a valid ip pool?

[Nuh_]

2 hours ago, technologicalpixel said:

yes the subnet mask is the same,

yes on the pc the ip address are taken automatically

 

but how do i check if the modem has a valid ip pool?

im guessing the subnet mask is 255.255.255.0

this means that the first 3 blocks of the ip (192.168.1) should be the same in the modem LAN and dhcp settings

[technologicalpixel]

you mean the first three block on the ip should be the same on the computers and on the modem? if you mean that yes they are the same when they are connected

[Nuh_]

3 hours ago, technologicalpixel said:

you mean the first three block on the ip should be the same on the computers and on the modem? if you mean that yes they are the same when they are connected

ok good

 

when the problem happens next time, check the IP your computer is getting (you can type ipconfig /all in cmd or through control panel) 

 

a solution might be to set a manual IP.

[technologicalpixel]

this is what i get when it's not working, i tried to set a manual ip but still doesn't work

ipconfig all.txt

[Nuh_]

11 hours ago, technologicalpixel said:

this is what i get when it's not working, i tried to set a manual ip but still doesn't work

ipconfig all.txt 1.18 kB · 3 downloads

the problem seems to be between the modem and the pc, because the pc is giving itself an APIPA address meaning it cannot reach the dhcp server on the modem, this would also explain why manual IP is also not working. 

 

tl;dr the pc can't get to the modem.

 

try changing the cable just to be sure that it's not the problem

if the cable isn't the problem, it could be the ethernet port on your computer or something wrong with your modem

judging by your initial explanation, I'll recommend checking the computer's ethernet port first.

[technologicalpixel]

but the fact is that happen with every pc connected to ethernet, so i should check all the ethernet port? 

 

also how i do check ethernet port?

 

another thing, i'm using some extremly long ethernet cables could that also be a problem?

 

also, can a broken ethernet port, interfere with other pc?

[Nuh_]

7 hours ago, technologicalpixel said:

but the fact is that happen with every pc connected to ethernet, so i should check all the ethernet port? 

and your wireless is working fine?

this seems like it's the modem

7 hours ago, technologicalpixel said:

also how i do check ethernet port?

you try another one, or use wifi and see if the issue is resolved; if so, then it's a problem with the ethernet

 

7 hours ago, technologicalpixel said:

another thing, i'm using some extremly long ethernet cables could that also be a problem?

depends on their length and type(cat5, cat5e, cat6, etc...). I would say, anything under 100m should be fine.

7 hours ago, technologicalpixel said:

also, can a broken ethernet port, interfere with other pc?

no

 

 

it seems to me that something is wrong with your modem's ethernet ports.

[Lurick]

What is the model of the modem? Do you have it connected to a router or does it have wireless built in?

If it's a modem only and not a combo unit then that explains this most likely.

[technologicalpixel]

it's a modem/router this one https://www.tim.it/content/dam/flytoco-areapubblica-aemfe/tim_it/assistenza/assistenza-tecnica/guide-e-manuali/c3/TIM-QG-SmartModem-Technicolor-A5-2016-3-17.pdf

 

yes wireless is working fine always on every device,

 

i have 3 cable 2 are long 50m and one is 2m all cable are cat 5e.

 

on all the computers i have only one port so i can't try other ports.

 

i would try to use other cables but i have to buy new ones, but the fact is that sometime is one pc and sometime is another one, so the only reason the cable don't work should be because they are too long not because they are broken, or am i wrong on that? anyway i'm passing 100m but from just 2m,

 

so yea as soon as i can i will try new shorter cables and let you guys know how it went, can i try something else meanwhile?

[technologicalpixel]

alright so i found an old cable and changed one of the longest and now seems to work!

[Nuh_]

1 hour ago, technologicalpixel said:

it's a modem/router this one https://www.tim.it/content/dam/flytoco-areapubblica-aemfe/tim_it/assistenza/assistenza-tecnica/guide-e-manuali/c3/TIM-QG-SmartModem-Technicolor-A5-2016-3-17.pdf

 

yes wireless is working fine always on every device,

 

i have 3 cable 2 are long 50m and one is 2m all cable are cat 5e.

 

on all the computers i have only one port so i can't try other ports.

 

i would try to use other cables but i have to buy new ones, but the fact is that sometime is one pc and sometime is another one, so the only reason the cable don't work should be because they are too long not because they are broken, or am i wrong on that? anyway i'm passing 100m but from just 2m,

 

so yea as soon as i can i will try new shorter cables and let you guys know how it went, can i try something else meanwhile?

no, you're fine with the cables, any individual cable shouldn't be more than 100m; you are at 50m so well below the limit

[technologicalpixel]

i don't know about that, from when i changed one everything is working! maybe was just broken, i have no idea but for now it's working